title: How often are MapQuest tiles updated with new OSM data?

text: When users make edits to OpenStreetMap, how long does it generally take for those edits to show up in the MapQuest tiles? Is this on the order of hours, days, or months?


title: Creating catalog of vector layers using ArcGIS Platform?

text: Is there a way to create a catalog of vector layers in ESRI? We have thousands of tiles of 25cm contour data which we need to individually find and add to maps. It would be so much easier if there was a way to load the best available tiles based on the current map extent. For Raster we use the Mosaic Dataset which works very well but is there a similar format for vectors? Mapinfo has hotlinks so we use the index tiles to open files in the frame without having to find the tiles but the best system is the Global Mapper Catalog (gmc) format which works great for vectors and rasters but a search online shows nothing for ESRI (the last mention of this though was in 2005). Any ideas?


title: ArcGISDynamicMapServiceLayer change layer hierarchy

text: I am building an application off an existing map server using the javaScript API. The server has about 10 layers that I am loading into my application as a ArcGISDynamicMapServiceLayer. Once I have loaded the layers into my application, is it possible to re-order their hierarchy? For example move the roads on top of the streams or move the parcels under the roads. I have already found that I cannot change the transparency of just one layer, and can only adjust for all layers at once. My guess is that it is not possible to reorder the layers from the browser. If this is the case how should I suggest my clients reconfigure their map server? Should each layer they want in the application be an individual mapService? Any other suggestions?


title: Can not import qgis.core in python

text: I installed OSGeo4W. I have no other Python version on my computer. I can `import osgeo`. But when I try to import `qgis.core` I am getting the error:               >>> import qgis.core     Traceback (most recent call last):       File "<stdin>", line 1, in <module>     ImportError: No module named qgis.core      What could be the reason for that?


title: Efficiently check for equal adjacent values in raster calculator

text: I have a raster consisting of integer values in each cell. I want to check every adjacent cell in a 3x3 grid to see if **any** one of the adjacent cells has a value EQUAL to the center cell, and if so, give the output raster a value of 1 (else give it a value of 0). I have already accomplished this like so:               Con("raster" == FocalStatistics("raster", NbrIrregular("C:\filepath\kernel_file.txt"), "MAXIMUM"), 1, 0)      Where the kernel file looks like this:               3 3      1 0 0     0 0 0     0 0 0       Then again for another possible combination:               3 3      0 1 0     0 0 0     0 0 0      And so forth:               3 3      0 0 1     0 0 0     0 0 0       Then I have to combine all of the rasters at the end to get one final raster. Is there a more efficient way to accomplish this? It shouldn't be necessary to loop through the raster this many times to get what I need. Raster calculator solutions will work, but ArcObjects solutions are welcome as well as the end result will likely end up being implemented in ArcObjects.


title: How can i use arcgis server services in arcgis viewer for silverlight?

text: I want to create a webgis using arcgis viewer for silverlight. i install arcgi viewer . when i want to connect to arcgis server service , the application show the error" unable to connect to "http://server name/ArcGIS/services/test". I copied clientaccesspolicy.xml into C:\inetpub\wwwroot but the application show same error . i tried "http://server name:8399/arcgis/services/test" but it doesn't solve my problem. i couldn't find any good help for this reason . what's my problem ?


title: How to handle interpolation of multiple (quality) tiers of irregular data?

text: I'm going to try to provide a high level overview of the issue - realizing that more details/info will be necessary - but I don't want to write a novel that seems too overwhelming for people to respond to :) **Background** : Let's say I have 3 sets (A, B, C) of irregular point data of varying quality; A is "better" than B and B is "better" than C. One or more data sets might have data for a given point. **Goal** : Create a grid/map that contains the "best" possible data. **Example/Possible Solution** : Use some sort of inverse distance weighted algorithm in combination w/somehow weighting the better datasets more than the lower quality data sets. Please feel free to post follow-up questions as I know my original post is rather vague. Thanks in advance.


title: Calculate Blue sky albedo from Black sky albedo and White sky albedo

text: I have got values for Black sky albedo and white sky albedo, from MODIS imagery. What is the simplest way to calculate blue sky albedo? I want to use albedo for snow cover. A website which has listed this formula: `Blue-sky (Actual) Albedo = White-sky Albedo * f(optical depth, solar zenith angle, aerosol type, band) + Black-sky Albedo * (1 - f(optical depth, solar zenith angle, aerosol type, band))` Now the thing is I don't have solar zenith angle, aerosol type etc.. What do I do? Please help


title: Restricting Tin interpolation in QGIS

text: I am trying to do a bathymetric map for a lake using QGIS. However, I see no option to impose a mask so interpolation does not extending beyond the boundaries of my lake. I have traced around the lake (polygon) to which I would like to restrict the interpolation. Is there a "set mask" function in QGIS that would restrict all subsequent calaculations? I know how to convert the polgon to raster if needed. I have cliped to the lake boundaries but it still runs over. Do I need to go to GRASS to do this? Using version 1.8 on Windows 7. Thanks Alyre


title: How can I add the frequency (count) of a point shape file on an animated map?

text: The problem is this: I have a crime (point) data on a map which is animated via time slider using a 1-week-period. I see all the points I added without a problem, I also added a dynamic text indicating the time period on each frame video shows. I just would like to add in a text (I guess this should also be dynamic) the count of crimes (points) on each time period (week). Thanks


title: QGIS [500]INTERNAL SERVER ERROR

text: My Name is Daniel and I'm from Indonesia. Short story recently I was learning how to set up qgis server. So here's the trouble I've encountered so far:   1. I was using OSGEO Live 5 Distribution ISO' Installed in dual boot mode with windows 7   2. I got the GetCapabilities work after fresh install. the response was as indicate in qgis server manual, the XML info about layer etc   3. After I execute update software system, then I tried to do the GetCapabilities returned 500 Internal Server Error. I didn't do any change in the qgis system which was worked fine before software update. What should I do to tackle this error * * * thanks for the tip mr unicoletti and to add that I'm very new to linux or foss, it just my work project have positioned me to like it or not to learn linux and foss. so I followed up advice I open the error.log have information such as following:               [Sat Dec 24 22:33:54 2011] [error] mod_fcgid: process /usr/lib/cgi-bin/qgis_mapserv.fcgi(1862) exit(communication error), get unexpected signal 6      [Sat Dec 24 22:33:59 2011] [warn] [client 127.0.0.1] mod_fcgid: error reading data, FastCGI server closed connection      [Sat Dec 24 22:33:59 2011] [error] [client 127.0.0.1] Premature end of script headers: qgis_mapserv.fcgi      [Sat Dec 24 22:34:05 2011] [error] mod_fcgid: process /usr/lib/cgi-bin/bik/qgis_mapserv.fcgi(1864) exit(communication error), get unexpected signal 6      [Sat Dec 24 22:35:10 2011] [notice] caught SIGTERM, shutting down      what the information state and a follow up action to take to troubleshoot the error. I also attached a link to the error.log file http://www.mediafire.com/?3zeuz48eeu8g8v1 thank you for kind people who help me...


title: GIS Consulting - How to Get a Foot in the Door?

text: I currently work for a very large company as a GIS developer, and while I am happy in my position for the most part, I can't help but wonder what life as a GIS consultant (i.e. working for myself) would be like... I know there are many excellent GIS consultants on this site, and I am wondering on how they got their start. Are there any good sites where companies and/or organizations post GIS related requests? Can they offer any strategies on how they market themselves to companies/organizations? Any other tips to test the waters per say? I'd also be interested in hearing about life as a GIS consultant. Any experiences or thoughts welcome.


title: Spatial+Temporal database request for 4D intersection

text: Here is the function I need to implement. My application deals with mobile objects with variable position and range (think of radar range). As I can't test each minute if n mobiles detect each other (server would be overloaded), I need to precalculate "future" position and time when they'll detect each other from their planned route and only register the "future" event in a stack. Each time a user changes the planned route, I'll recalculate event related to all intersecting routes from other mobiles. The best way to do that is to make a kind of 4D intersection request and update, and be able to detect when and where mobiles will "collide". Is it possible with a classic geodatabase like PostgresQL+PostGis and another plugin, or do I need to look at specific n-dimensional database ?


title: how to show information window for the marker cluster

text: This is my markercluster code : i need information window for the markercluster icon as well as marker icon, i have another cluster.js file, can some one please tell me how can i show the information window for cluster icon when single mouse clik, and same for the marker icon               function initialize(doc) {         var mapDiv = document.getElementById('logitmap');         var latlng = new google.maps.LatLng(37.4419, - 122.1419);         var options = {             center: latlng,             zoom: 2,             mapTypeId: google.maps.MapTypeId.ROADMAP         };         // Creating the map         map = new google.maps.Map(mapDiv, options);         bounds = new google.maps.LatLngBounds();         var jsonData = eval("(" + doc + ")");         var markers = [];         var markerIconURL;         markerIconURL = jsonData[0].markerIconURL;         for (var i = 1; i < jsonData.length; i++) {             var input = jsonData[i];             var gtype = input.Gtype;             if (gtype == "marker") {                 var latLng = new google.maps.LatLng(input.latitude, input.longitude);                 var marker = new google.maps.Marker({                     position: latLng                 });                 markers.push(marker);             }         }         var markerClustererOptions = {             imagePath: markerIconURL,             zoomOnClick: false         };         var markerCluster = new MarkerClusterer(map, markers, markerClustererOptions);     }


title: Automate “add junction flag-->trace downstream-->update field”

text: I have two point feature classes in a geometric network, say featureA and featureB. FeatureB is downstream of featureA. And there are about 10 featureB points downstream of 1 single featureA point. I need to update a field in featureB base on a field in featureA after trace downstream by selection. I can do this manually by place “add junction flag” on individual point in featureA, and trace downstream by selection. Then update the field in selected featureB points(fieldB2) based on the value in featureA field(fieldA1). The problem is: I have 2000 points in featureA. I would have to repeat above process 2000 times. Since it’s a repetitive process, is there any way I can automate this.   1. If FieldA1 is not Null: place a junction flag-->trace downstream by selection   2. Update selected fieldB1: FieldB1=FieldA2 Thanks


title: Count gaps between polygon in spatialite

text: I have a database (.db) with a table that contains thousands of polygons containing id and geometry. I like a query that can get me the 'number of errors where there are gaps between polygons". How can I prepare such a query ? What GIS function I can use ? let's suppose table structure :: table name : temp1 column name :: id (integer) : POLYGON_ID geometry


title: Using GeoServer REST API and C# to create Layer Group

text: Following information at this link in the section on creation of layer groups, I've created the method(C#):               public bool AddToLayerGroup(string layerGroupName, string layerName)             {                 try                 {                     string gUrl = GEOSERVER_HOST + "/rest/layergroups";                     WebRequest request = WebRequest.Create(gUrl);                          request.ContentType = "application/xml";                     request.Method = "POST";                     request.Credentials = new NetworkCredential(GEOSERVER_USER, GEOSERVER_PASSWD);                          byte[] buffer = Encoding.GetEncoding("UTF-8").GetBytes(GetAddToLayerGroupXml(layerGroupName, layerName));                     Stream requestStream = request.GetRequestStream();                     requestStream.Write(buffer, 0, buffer.Length);                     requestStream.Close();                          WebResponse response = request.GetResponse();                          return true;                 }                 catch (Exception)                 {                     return false;                 }             }      When I run a unit test against this method, I get an `Internal Server Error` reported from GeoServer if I use `POST` HTTP method. Now the `layerGroupName` and `layerName` used in the above method are already existing in GeoServer. What I want to achieve is provide a way to create a layer group if it doesn't exist, or just use an existing one. The `layerName` always already exists in GeoServer, as I'm using a separate method to create them. Can anyone spot any problem with my code above. Or, suggest an alternative approach. cURL or Java or C# examples are welcome. Thanks in advance. UPDATE: From Tomcat logs, GeoServer complains that the layer group I've specified already exists. Is there away to add a layer to an existing layer group using the REST API?


title: ArcGIS iteration naming

text: I'm trying to use the iteration function in ArcGIS model-builder. To avoid overwriting the output raster, I used %Name% inline variable. But the name of my files are getting bigger and bigger overtime (I use the outputs in another set of iterations). Is there a way to select only part of the file name and not all of it? Thanks


title: Exporting attribute data from vector data by selecting object in QGIS?

text: I'm using QGIS (2.4.0), and i need to export the attribute data of the object i select (shapefile) to another file ( Excel, txt,...it is yet to be determined depending on the solution). I know how it is done manually, but this action has to be done over a thousand times, and it can only be done one object at a time... I'm looking for a automated proces where just by selecting a object the attribute data is written on the fly into the other file. Does anyone have a solution, or an easy workaround, for this?


title: Generate MBTiles from xml

text: I need to generate hundreds of MBTiles from different shapefiles and same styles, so I created a xml from tilemill with a single shapefile and styling, using python landez library to generate MBTiles from this xml (keep changing datasource for each shapefile). Problem is landez is taking too long to create while tilemill is faster in exporting MBTiles, also through landez, few tiles are missing at different zoom levels (blank tile, so default color). I was just wondering if this can be done using tilemill, (tilemill seems to export only projects). PS: I want to do this process through terminal.


title: Openlayers heat map not displaying properly in html

text: I was wondering if you could help me with something I am trying?? Created a heatmap from a sql point table using sld in GeoServer. Displays fine as a preview:- It looks tiled when I publish it to the web mapped:- Here is my HTML Code:-               <meta charset="utf-8">     <script src="http://www.openlayers.org/api/2.11/OpenLayers.js"></script>     <script>                        var map, layer;              function init(){             var epsg900913 = new OpenLayers.Projection("EPSG:900913");             var epsg4326 = new OpenLayers.Projection("EPSG:4326");             var cent=new OpenLayers.LonLat(143.841243,-37.833563).transform(epsg4326,epsg900913);                                                      var osm = new OpenLayers.Layer.OSM("Open Street Map");                                                      awms = new OpenLayers.Layer.WMS("GPS Boundary", "http://172.16.3.68:8080/geoserver/GPS/wms",                 {                     version: "2.5.2" ,                     layers: "GPS:LGA_POLYGON_GPS",                     transparent: true,                     tiled: true                 },                 {                     visibility: true,                     sphericalMercator: true,                     displayOutsideMaxExtent: true // Will not appear with certain zooms without this option                 }             );                                                      bwms = new OpenLayers.Layer.WMS("House Points", "http://172.16.3.68:8080/geoserver/GPS/wms",                 {                     version: "2.5.2" ,                     layers: "GPS:House Points",                     transparent: true,                     tiled: true                 },                 {                     visibility: true,                     sphericalMercator: true,                     displayOutsideMaxExtent: true // Will not appear with certain zooms without this option                 }             );                  cwms = new OpenLayers.Layer.WMS("Animals Heatmap", "http://172.16.3.68:8080/geoserver/GPS/wms",                 {                     version: "2.5.2" ,                     layers: "GPS:Animals",                     format: 'image/png',                     transparent: true,                     singleTile: true,                      ratio: 1                 },                 {                     visibility: false,                     sphericalMercator: true,                     displayOutsideMaxExtent: true // Will not appear with certain zooms without this option                 }             );                            map = new OpenLayers.Map("map",{                 layers:[osm,awms,bwms,cwms],                 center: cent,                 zoom: 10             });                                                      var switcherControl = new OpenLayers.Control.LayerSwitcher();                                                 map.addControl(switcherControl);                                                 switcherControl.maximizeControl();      //Variable Scale Bar var scaleline = new OpenLayers.Control.ScaleLine({ div: document.getElementById("scaleline-id") }); map.addControl(scaleline);                                                           map.addControl(new OpenLayers.Control.MousePosition({element: $('location')}));                                                      }                        </script>      ![example of in HTML](http://i.stack.imgur.com/AP1GG.png)


title: Creating blended colour relief in QGIS?

text: I am mapping mountainous areas in QGIS 2.4 and would like to recreate the beautiful blended colour relief found, for example, in the map shown at http://maps.kartoza.com/Boosmansbos/. While I am able to copy the RGB values of the colours from the key at the side of the map, and map them into my own elevation bands, I am unable to recreate the 'blended' effect between the elevation bands as QGIS produces a 'hard' line between elevation levels. * * * I'm using the basic mode I suppose which is the menu at the top, Raster - Terrain Analysis - Relief, then mapping the colour bands that way. I thought I might be able to get a 'blend' by overlapping the elevations slightly in each band, but it doesn't seem to let me do that.


title: QGIS 2.2 - spectral profile for multilayer/time series

text: I am missing a spectral profile in QGIS which enables me to see the values for all bands of a given pixel. (absolutely necessary for multispectral and multitemporal/time series work) It seems, there has been such a plug in called "earthbeat". http://hub.qgis.org/projects/earthbeat/wiki This is exactly what I need, but the plugin seems to not work for QGIS 2.2 . It should be in the official repository. Am I getting anything wrong? Thanks for help and clarification.


title: export map state as JSON: Web_Map_as_JSON

text: Is there a way to export the current map state as a JSON object, mostly named **Web_Map_as_JSON**. The JSON specification should be like this. In other words, it would be convenient to have a function for the Map object, like myMap.Web_Map_as_JSON() that would provide the current state of the MAP.


title: conversion from .osm to .map with mapwriter plugin fails

text: I have a problem with Osmosis v 0.43 with mapsforge mapwriter plugin 0.3.0. on Windows. A command               osmosis --read-xml file=C:\geo\testmap.osm --mw file=C:\geo\genmap.map     bbox=0.0,0.0,51.9,19.2      fails with error:               SEVERE: Thread for task 1-rx failed     java.lang.AbstractMethodError:     org.mapsforge.map.writer.osmosis.MapFileWriterTask.initialize(Ljava/util/Map;)V     at org.openstreetmap.osmosis.xml.v0_6.XmlReader.run(XmlReader.java:95)     at java.lang.Thread.run(Unknown Source)      I tried using --rx with --wx and obtained no errors, so something must be wrong with the mapwriter plugin. Using earlier version of Java did not work, as I suspected it could be a java related problem.


title: How to use Mapserver+Openstreetmap for tracking service effectively?

text: I have got Asset tracking installations for many clients. The availability of GIS map data for every client location seems to be the tough part. I have got a MapServer WMS installation. Can I use OSM data behind mapserver? Also I need to timely update with latest OSM data.   Is there any mapfile (MapServer map style configuration file) for OSM data?   And is PostgreSQL/PostGIS also a better option to include? Update: I followed exactly the instructions on http://trac.osgeo.org/mapserver/wiki/RenderingOsmDataUbuntu as advised by mapper. Everything worked fine. Got the osm-gooogle.map. But, when I browsed `http://localhost/cgi-bin/mapserv?map=/var/www/osm-demo/mapserver-utils- svn/osm-google.map&mode=browse&template=openlayers&layers=all`   There was few things to change in the generated mapfile. Mainly, the IMAGEPATH & IMAGEURL were inside METADATA tag. Moved them outside to WEB tag and everything worked fine. It started drawing Google styled map from OSM data stored in local PostGres DB.


title: Creating fishnet from template feature class using ArcPy?

text: I can’t use the tool arcpy.CreateFishnet_management because define the parameter “templateExtent” with a shapefile it is not filling automatically the parameters “originCoordinate” and “yAxisCoordinate”.               import arcpy     from arcpy import env     env.overwriteOutput = True     env.workspace = r"D:\Users\julia\erste_aufg"          #Process: Create Fishnet     outFeatureClass = r"D:\Users\julia\erste_aufg\at001l_wien\at001l_wien\wien.shp"     cellSizeWidth = '200'     cellSizeHeight = '200'     templateExtent = r"D:\Users\julia\erste_aufg\at001l_wien\at001l_wien\at001l_wien.shp"          arcpy.CreateFishnet_management(outFeatureClass, "", "", cellSizeWidth, cellSizeHeight, '0', '0', "", "NO_LABELS", templateExtent, "POLYGON")      ![enter image description here](http://i.stack.imgur.com/u5vKo.png) It is working in the ModelBulider, so something is running in the background of the ModelBulider that it could create the parameters “originCoordinate” and “yAxisCoordinate” when it has a “templateExtent”. How can I get this tool running in ArcPy by having just the parameter “templateExtent”? I would be really happy if someone has a solution because I need the Fishnet in a scripttool and cannot go one without because in the end there is a loop so the values of the extent are always different. the first part of the whole script


title: Arcobjects/Arcgis Engine -- geoprocessing within a buffer?

text: I have a point layer and a polyline layer (each contains more than 100k records), I would like to process the polyline layer within point buffer zones. For example, for each point in the point layer, identify polylines that within a 10m buffer zone and calculate point-to-line distances. It would be something like:               for point in points_layer:         create a 10m buffer;         identify polylines that intersect with the buffer;          do point-to-line distance calculation;      Is there a way in AO/AE to do geoprocessing within buffer zones? Thanks!


title: How to calculate total number of data cells in raster?

text: I am using ArcGIS 9.3 and python 2.5. My code is shown at the bottom of this post. I have a raster containing fire intensity information at 200m cell resolution. I run the script and the first count cell part returns the size of the fire. This works fine. I then clip the raster using a polygon representing a forested catchment. The new raster represents the area of the catchment that is burnt. When I try to use the same code to count the number of cells of the new raster, it always gives me an answer of zero, even if there is definitely a raster created by the clip tool. I have tried every combination of every tool I can think of. my code...                   fire = str(ignitionID) + "_" + str(weatherID) + "_Intensity.asc"         print "fire: " + fire              # ---------------------------------------------------------------------------         # this section calculates the size of the fire for model calibration purposes         # ---------------------------------------------------------------------------              # Process: Build Raster Attribute Table...         the_fire = input_fires + fire         shutil.copy(the_fire, "C:\\FIRESTORM\\Workspace") # copy the fire to workspace         the_fire = "C:\\FIRESTORM\\Workspace\\" + fire              try:           gp.BuildRasterAttributeTable_management(the_fire, "NONE")           resultf = gp.GetCount_management(the_fire)  # count num of rows in raster           countf = int(resultf.GetOutput(0))           fire_area = countf * 4  # each cell has an area of 4 ha           print "the fire area = " + str(fire_area) + " ha"              except:  # the attribute table cannot be created coz the fire is too large                fire_area = 300000 # default value for large fires 300000 ha           print "the fire area EXCEEDS 262,140 ha"              # -----------------------------------------------------------------------------         # this section calculates the area of the catchments that are burnt by the fire         # -----------------------------------------------------------------------------              # Local variables...         catch_extent = input_catch + "WS_Catchment_region.shp"  # catchment boundary         fire_raster = "C:\\FIRESTORM\\Workspace\\fire_raster"         fire_ascii = the_fire         Output_raster = "C:\\FIRESTORM\\Workspace\\Extract_ASCI1"         Output_ASCII = "C:\\FIRESTORM\\Workspace\\rastert_extract1.asc"         catch_burn_area = 0  # reset catchment burn area              # Process: ASCII to Raster...         gp.ASCIIToRaster_conversion(fire_ascii, fire_raster, "INTEGER")              # Process: Define Projection... based on projection of catch_extent         desc = gp.Describe(catch_extent)         spatialRef = desc.SpatialReference         gp.DefineProjection_management(fire_raster, spatialRef)              # Process: Extract by Mask...         gp.ExtractByMask_sa(fire_raster, catch_extent, Output_raster)              # Convert raster to ascii         gp.RasterToASCII_conversion(Output_raster, Output_ASCII)              # Process: Build Raster Attribute Table...         gp.BuildRasterAttributeTable_management(Output_ASCII, "OVERWRITE")              # count number of rows in raster         resulti = gp.GetCount_management(Output_ASCII)         counti = int(resulti.GetOutput(0))         catch_burn_area = counti * 4  # each cell has an area of 4 ha              print "catchment area burnt = " + str(catch_burn_area) + " ha"


title: QGIS 2.0 Table Join creates unwanted prefix in field names

text: I used to join shapefiles and CSV files via the "joins" tool in the layer properties just fine in QGIS 1.8 . Now i've updated to QGIS 2.0, and when i do the exact same thing, QGIS puts the name of the CSV source as a prefix in the field name: for example instead of just naming the field "area" it's now labelled "sourcefile_area". I googled it, and searched in the qgis settings, but didn't find anything that helped. maybe I just don't know what exactly to search for though. Thanks in advance! Greetings Gunnar


title: Is it possible for Geoserver to create a WMS that pulls red, blue, green channels from different data layers?

text: If I have three separate raster datasets available in my GeoServer instance, each with one channel of 8-bit unsigned int values, is it possible for me to somehow create a single WMS service that pulls the red, green, and blue channels from these three separate sources? The way I am doing this now is to use gdal_merge.py to combine the three data sources in advance and then store the rgb output product as its own data layer with its own WMS service. If possible I would prefer to combine the channels on the fly at the time of a WMS request. I know that generally, rgb channels can be defined for a WMS using a colormap, but I've not been able to find any way to pull from multiple datasets within a single colormap. Any ideas? I realize this is an unusual thing to want to do in the first place but you'll just have to trust that I have my reasons.


title: Multiple script hyperlinks not loading in ArcGIS

text: I've set up my layer to use hyperlinks based on a script. When I use the Hyperlink tool and click on a link, often times it loads just fine. ![enter image description here](http://i.stack.imgur.com/BoMPG.png) The problem I have is when there are multiple points on top of each other, each with their own hyperlinks. A window opens that allows me to select the hyperlink I'd like to use. The problem is, I can't seem to activate the hyperlink. Note that these links are used by a script hyperlink. That's why they aren't websites or document paths. I've tried selecting the link, and clicking "Jump". I've tried double-clicking the link. I tried pressing "Enter" on the keyboard. I tried the Space Bar. Nothing seems to activate the links. Are multiple script links from multiple points not supported in ArcMap 10? Is there another way to activate these links that I haven't thought of yet?


title: Why are there blank in the ST_AsGeoJSON results?

text: I have a vector layer tipor several polylines. I opened this layer in QGIS and exoportar to a spatial table in PostGIS. ST_AsGeoJSON want to use the function to get the GeoJSON to draw on Google Maps. I used the select below:               SELECT ST_AsGeoJSON (geom), Codlin         FROM "lines";       I noticed that in the result column st_asgeojson few lines comes in white and records that return blank geom field of the table space is blank. I think some records of my table are not georeferenced. How can I fix this error?


title: Easily calculate "roundness/compactness" of a polygon

text: I am trying to find ways to quantitatively describe the shapes of various polygons. For my project, these polygons represent lakes, rivers, lagoons, and parks. So they can be almost any shape. One easy metric is to calculate perimeter vs. area, which is at best an only slightly useful metric. But I would also very much like to be able to say something about the 'roundness' of a polygon. Or how 'compact' the shape is on a map. The only way I can think of doing this easily is to calculate the area of each polygon in relation to a bounding box for that polygon (which I already have). But this seems like a poor solution. So now I am thinking of something more like this - take the centroid of the polygon, add on a series of buffers of increasing areas (say 50%, 100%, 150%), then compare how much overlap there is between each buffer and the original polygon. A perfect circle will have perfect overlap at 100%, and I can use the 50% and 150% buffers to judge how much and in what way each polygon differs. But even that feels cumbersome, and like a poor workaround for what somebody else has probably already figured out far better. If anyone can point me in the right direction, I'd greatly appreciate it. For reference, at a minimum I will need to be able to look at the resulting indices for the shape of various polygons, and be able to make an educated guess as to their source (River? Reservoir with dendritic shape? Lake/Lagoon? Park?)\


title: Add Custom Data to OpenLayers Plugin for QGIS

text: Is there a way to add custom data to the OpenLayers plugin for QGIS? I have tiled data using Map Tiler, which has produced my zoom levels, and an OpenLayers.html. I am hosting it internally on our servers, and I would like to access it from the OpenLayers plugin. Thoughts on where to start? Thanks...


title: Can you change the processing extent in environment settings using python to a shapefile?

text: I have managed to do this manually at Geoprocessing>Environments>Processing Extent and setting the shapefile in the drop down bar. I was wonder if this could be automated with a python script? My goal is to create a loop to change the processing extent prior to using spatial analysis tools on a various rasters that represent the areas of the shapefiles. This will keep their extent size minimal. Edit (Current Code): (Not working)               for i in range (31):     ... arcpy.env.extent = (r"C:\Folder\Shapefile"+str(i)+".shp")      Receiving a runtime error stating "Error in accessing environment "


title: Download mapbox default style as tiles

text: I need to have the tiles of a small city as PNGs. The style should be the same as in https://www.mapbox.com/editor/? Can I export the map there for a certain bounding box to tiles (or mbtiles)? I have setup a project but export to mbtiles or tiles does not seem to be available. Or is it (as a workaround) possible to export just the mapbox default style in order to use this style with TileMill? I have seen the OSM Bright style, but I am not sure: Is this the same style as the default mapbox style?


title: Pgrouting, pgr_dijkstra function error

text: I'm starting to use the Pgrouting function on my database Postgresl. I have the table of links (id, source, target, cost) which contains the set of edges of my graph. I want to calculate the shortest path of a given node to another. The `pgr_dijkstra` function returns an error that I have not understood. Here is the table of edges: ![The table of edges](http://i.stack.imgur.com/Lrzw9.png) When I'm trying to run this request:               SELECT seq, id1 AS node, id2 AS edge, cost     FROM pgr_dijkstra('SELECT id, source,target, cost FROM ubanlinks', 244225135, 598385915, false, false);      It returns this error: > ERREUR: Error computing path: Unknown exception caught! ********** Erreur > ********** ERREUR: Error computing path: Unknown exception caught! État SQL > :38001 Does anyone have an idea as to what is the problem of my request or my table?


title: GWR and OLS regression models

text: I'm somewhat confused about regression models. I decided to create a GWR model for a project using 35 polygons of health data. However I find now that my model has flaws and I cannot create a GWR model probably because the dataset is too small. When creating a OLS are we meant to remove all variables that are related? if I'm modelling obesity, I would think that income, exercise are factors that relate to it so what purpose does the OLS model serve? I created a model after removing auto correlated variables but I'm kind of confused as to what its meant to be showing.


title: How can I define the extent setting of environments programmatically in VBA?

text: I use the following line of code to define the extent setting of the environments GP.Extent = "144566.589424822 351191.130242809 145772.160224822 353810.742942809". However, I need to define it programmatically via the boundaries of a layer like the procedure is carried out in any relevant window (e.g. in Clip window) :'Environments'-'General Settings'-'Extent'-'Same as layer...'. Thanks Demetris


title: Difference between network dataset and geometric network

text: In ArcGIS, what is the difference between a "network dataset" and a "geometric network"? Are there differences with what can be done with each?


title: Realtime traffic data provider(s)

text: What services provide realtime (or daily-updated) basic traffic informations for Western Europe ? For example, traffic.com/Navteq provides such data to Bing Maps for US/Canada and Microsoft suggests CENTRICO/OTAP for Europe in its documentation (which is outdated, EasyWay seems to have replaced this service), but its website is slightly confusing. Are there other major actors in this market for Europe ? * * * For example, One Step Ahead seems to provide [free] data for Germany, Netherlands and Belgium, but it's a single file per country (hence not tiled data), and I'm not sure how often it is updated.


title: Help needed for extended symbol

text: I am trying to extend Symbol class in ARGIS Flex API. this is my widget named TestWidget http://pastebin.com/04w6RSur and here is the extended symbol class http://pastebin.com/bqhDzdSe named CustomSymbol placed in Test package in flexviewer 2. I had drawn a circle and a line in CustomSymbols sprite like this:               sprite.graphics.beginFill( 0x0000FF,1 );     sprite.graphics.drawCircle(0,0,100);     sprite.graphics.endFill();       sprite.graphics.lineStyle(5,0xFF0000,1);     sprite.graphics.lineTo(mapPoint.x+100,mapPoint.y+100);      when I zoom into map it shrinks its size and when I zoom out it grows accordingly. What I want is make it retain its size whether I am zooming in or zooming out. Thanks


title: Join attributes of point and line layer by location (closest distance) in QGIS

text: My problem is the following: i have a line shp (target layer) and a point shp (join layer). the second one (point layer) holds an attribute which i want to join with a line layer based on closest distance to the line. Points and lines are not intersecting I can do this with arcgis and spatial join(match option: closest), but i don't know how can i achieve this in Qgis. I'd really appreciate an answer for this. Miha


title: mapserver postgis

text: I have a problem with my connection to my db. I get this message: `msPostGISLayerOpen(): Query error. Database connection failed (fe_sendauth: no password supplied ) with connect string 'host=localhost user=postgres dbname=ejemplo'Is the database running? Is it allowing connections? Does the specified user exist? Is the password valid? Is the database on the standard port? msDrawMap(): Image handling error. Failed to draw layer named 'municipios'.` I have no password set on my db and I don't know why I can't connect with it.


title: labels showing up behind other labels due to unmatched z-index

text: I am using leaflet label plugin to show labels on markers by using `layer.bindLabel('name')`. As the number of markers is high the markers come above the label thus labels are not visible clearly. ![enter image description here](http://i.stack.imgur.com/wMy0q.jpg) Seems marker and its label have same z-index. I tried changing the z-index of marker by `.leaflet-marker-icon{ z-index: 1000;}` and also that of the label `.lealet-label{z-index: 1001;}` but still the result is the same and the z-index of marker is not changed either. What would be solution to this problem?


title: Make feature layer based on date, problem in python

text: I have a script that runs, that takes the current date and puts into a variable, which is then used to calculate the date field for the Feature class. Further in the script, the updated data is loaded into the live SDE feature class. The old data get deleted with the following task. 1 - Make Feature layer, where the date field is not equal to the date variable. 2 - Delete these features. My problem is that the to create feature layer is empty as i can't get the syntax right. I have tried the following               gp.MakeFeatureLayer(myOutputConnexion + os.sep + "SY_PLN_MON_INFO.LLPG_POINTS","OLD_LLPG_POINTS","GIS_TIMESTAMP <> TO_DATE('" + ExactScriptTime + "00:00:00' ,'YYYY/MM/DD HH24:MI:SS')")      and                   gp.MakeFeatureLayer(myOutputConnexion + os.sep + "SY_PLN_MON_INFO.LLPG_POINTS","OLD_LLPG_POINTS","GIS_TIMESTAMP <> TO_DATE(' + ExactScriptTime ','YYYY/MM/DD HH24:MI:SS')")      The ExactScriptTime variable value is 21/08/2012 13:00:07 (which gets created in at the start of the script). I know that the feature layer is empty because i have exported the feature layer into an FC, and it is empty. Has anyone got any ideas on where I am going wrong. Thanks


title: Are There Any OpenSource GIS Software Programs With an "Interactive" Rotate Feature Option?

text: ![Rotate feature option][1]Sorry if the question is too simple, but are there any open source GIS software programs available with an interactive "Rotate vector feature" option? Eg : ArcGIS has it in Editor\Rotate. Manifold has it in Transform toolbar (but its only angle based, not interative) . Any help is appreciated.


title: Correct Use of MBTiles PHP Script

text: I have installed the OSGeo4W web server tools on a Server 2008 machine, and I would like to serve MBTiles to Leaflet. I have tried these: Zverik's mbtiles-php Infostream's mbtiles-php fork The required php files and .htaccess were placed in a directory under \htdocs and Apache happily serves files from there. However, I am unable to form any URL that retrieves tiles. Firebug shows a '200 OK' on the tile request, but no content. Given that the mbtiles database and the script reside in a directory called 'mbtiles', can anyone inspect the scripts and explain how to properly form the URL? A proper L.tileLayer string for Leaflet would also be accepted. Also, any other minimal configuration solution (that will run on the OSGeo4W install) that will serve my .mbtiles to Leaflet would be accepted. Thanks -tom


I am using PyQGis API to create a custom application. How do I allow users to select features with the mouse? Is there a mapTool for this? Surely with a product as powerful as QGis there must be. Thanks in advance


title: How to view attribute table in layer within ArcGIS Server map service?

text: I'm new to ArcGIS Server and am trying to publish layers within an mxd to ArcGIS Server. When I bring the published map service back into Arc there is no Open Attribute Table option although I am able to identify the data. Is there away of displaying the attribute table?


title: Can't pan around my OpenLayers map .. unless there are no Layers under the mouse

text: So I've got my map displayed and some `Features` added to a `Layer`. All good, etc. When I try and pan around my map, I can only pan when I left-click the mouse .. hold .. and drag the mouse ... when the mouse cursor is NOT over a feature/shape on the vector layer. Otherwise, the panning works great. What's the trick to say .. can pan the map at any time / anywhere the mouse cursor is?


title: ArcScene3D layer rendering problem

text: I'm having problem with ArcScene. I'm doing a project on the visual impact of felling areas of forest in locations regularly visited/used by people. I have viewpoints and have created a TIN model for ArcScene. However when i try to drape my other layers - forests, roads, viewpoints - some become patchy and disappear beneath the surface of the TIN in ArcScene. I have tried converting these features to 3D, adding layer offsets and extruding features but they just seem to make the imagery worse. I have also set the drawing priority to its lowest for the TIN and all others layers' priority to their highest.


title: QGis : superimpose 2 rasters georeferenced (adjustment)

text: I am pretty new in QGis and I encounter the following problem. I have 2 rasters, let's say, "cadaster" and "tranchot". The raster "tranchot" was georeferenced from the raster "cadaster" with QGis. After the georeferencing, QGis shows the 2 rasters perfectly superimposed and built on the same projection. Today, I want again to superimpose this 2 rasters but "tranchot" looks like a thumbnail in the corner of "cadaster". From the metadata, the pixel makes 0.1143 meter for "cadaster" and 0.02831 meter for "tranchot". Probably there is an handling to be done in QGIS to superimpose these two rasters, probably simple, yes, but which one ? In the future, I'll need to compare vectors from "cadaster" with the raster "tranchot". Is there a mean to make rasters and vectors superimposable permanently ? Many thanks in advance for your help


title: osm2po: access values of maxweight tag

text: What is a best way to access osm's maxweight tag value to be able to use it in edge router? Basically my goal is to overwrite EdgeRouter's calcEdgeCost and check there if given edgeIdx has maxweight tag and if yes then act upon value of that tag.


title: Add WMS layer in existing map with ArcGISDynamicMapServiceLayer

text: We have an existing Silverlight application that loads a ArcGIS MapService and display it to the user. We want to add the ability to also add a WMS layer on top of the existing displayed map. I am not too familiar about WMS layers and the samples i found on ArcGIS are only loading ArcGIS WMS layers. We have updated one of our ArcGIS map services and enabled the WMS capability. How do i add the WMS layer to the map? Would i access it the same as a ArcGISDynamicMapServiceLayer? using a url like this? `http://OurArcGISServer/arcgis/services/Map1/MapServer/WMSServer` Any input is greatly appreciated.


title: Trying to create an app with an editable layer for iOS users, confused on next step!

text: I've recently started an app mapping project in which the end goal is to allow a user to have an editable layer on top of an already existing map. I'm trying to do this with open source information and also where I will be able to look at all the edits users suggest and moderate them. I'm a little hung up on what direction to head in to have map interactivity. Basically I want someone to be able to TAP the map and draw points/lines which will snap to existing features and be stored elsewhere to be added to the master map if said changes are correct. I have QGIS, Tilemill, and I'm looking at Leaflet (although it appears that the plugins are only good for mobile friendly viewing and not necessarily mobile iOS development). Are there open source things of this nature already out there. Any help or advice is greatly appreciated :)


title: How to measure the distance of multiple points to a line

text: I have two shapfile in QGIS to which I am trying to find the distances between. I have a shoreline which is a vector line and then I have hundreds of data points in the ocean. What I am trying to find is measuring the distance of each point to the corresponding place horizontally on the shoreline thus giving me a distance of each point from the shore. I have tried the distance matrix plugin which seems to only deal with point to point distances and have tried the mmqgis hub distance which only measures distances to a central fixed point on the line. Is there a plugin or way to find the distances I am looking for?


title: How do I create a polygon with an ArcGIS 10.1 python addin

text: I'm looking for some code samples, or help with code to get me started. I've built a python addin menu which I would like to use to create polygon features in a specific layer in my edit session. ![enter image description here](http://i.stack.imgur.com/4ujcO.jpg) So for example I would click 30x60 and a 30m x 60m rectangular polygon would be placed where I click. I can't seem to find much on creating geometry within a python addin. Thanks in advance for any comments or suggestions. Frank


title: Export layer with symbology with open-source tool

text: Similar to ArcGIS's "Layers", and "Layer packages", are there any open-source analogs? If I have a PostGIS table opened in QGIS (or GRASS, etc.), can I export it WITH the data, as well as with a symbology definition, etc. I want to send a layer to someone that they can open in Arc/QGIS/GRASS/etc. which will retain the symbology and labeling that I setup on my end. Can this be stored within a PostGIS table? Thanks.


title: ArcGIS Metadata validation

text: I have been importing metadata from an xml file generated with an xslt transform. During the import process, ArcGIS attempts to validate the metadata. It gives a number of cryptic validation warnings such as: **Validation failed: em:maintenanceAndUpdateFrequency($_, $a) --> em:lookupCodeName($a, gmxRes:MD_MaintenanceFrequencyCode)** I can't seem to find out much about what this means - there is a tantalising page on the ESRI help site (see third bullet point of Usage), but that's all it is - tantalising! Is this validated using ESRI's own software or something, because there seems to be little documentation about what it means, which isn't that helpful. Or is it a standard XML validation output?


title: dojox.geo.openlayers roadmap?

text: I'm curious as to the future of dojox.geo.openlayers. Presently is seems only to be a solution for positioning widgets on the map but I can imagine developing a suite of map specific dijits such as TOC, filtering, measuring and editing tools and on and on. Is anyone aware of (or willing to share) a roadmap for future dojox.geo.openlayers work or knowledge of other openlayers dijits?


title: Difference between server and geospatial server

text: I have been working with Geoserver and ArcGIS Server but I am still not sure what make these geospatial server handle the spatial data transfer compared to the normal server, like apache & jetty, on which these are installed? What is that factor that makes Geoserver and ArcServers to be spatially enabled?


title: Is ArcGIS 10.1 Desktop compatible with 10.0 Server?

text: Since upgrading my "ArcGIS for Desktop" (Windows 7) client to 10.1, I'm having the hardest time trying to figure out how to publish a Map Service on my (CentOS) 10.0 Server. Back on 10.0 Desktop, I would just load up my .mxd, use the Map Service Publishing toolbar to make a .msd, and then FTP the .msd with the data (it's contained in a file geodatabase) to the server and start a new map service in Server Manager. Easy! Now the "Map Service Publishing" tool has changed into a completely different "Publishing" tool. If I skip the .msd and try to publish just the .mxd with the FGDB, the ~~map is blank~~ server says the format of the MXD is invalid. I can't be the only one in this situation, but I don't see any Desktop<->Server compatibility information on 10.0 and 10.1. I don't know if I'm just doing something wrong or the two products really aren't compatible.


title: Problem with panning and zooming in OpenLayers

text: I'm interested in detecting when a user moves or pans a map so that I can run a new query on a database based on their location. However, the following code causes the panning and zooming controls to go crazy:               map.events.register("moveend", map, function(){                       getValues(map.center);                        });      If I comment out these lines, there appears to be no problem. If they are included, after two pans or zooms, the map suddenly jumps to half-way around the world (it looks similar to 0 lat, 0 long). I'm unsure what I am doing incorrectly. The other problem I have regarding the pan/zooming is that the `movend` does not really seem to wait until the user has finished moving or panning. Queries seem to be fired off even as the map is being moved and panned. Again, I'm not sure if this is a problem with how I am detecting this but it does not seem to behave as I thought it would. EDIT: Including `getValues` function also:               getValues = function(c){              c.transform(map.getProjectionObject(), new OpenLayers.Projection("EPSG:4326") )         console.log(c.lat, c.lon)              $.ajax({                  type: "POST",                 url: "php/query.php" ,                   data:{x: c.lat, y:c.lon},                   async: true,                 success: function(r){                         console.log(r);                 },              dataType:'json'             });               }


title: Load layers only when zoom level is reached

text: I'm trying to load different layers based on the user zoom level with OpenLayers. I've seen some similar questions in here, but they load the layer and then hide/show it based on the zoom level. I don't want the layer to be loaded. I've managed to use some answers and came with a solution, but I don't like it that much. There must be an easier way. Can anybody point me in the right direction? Here is the solution I've found so far.               map.events.on({ "zoomend": function (e) {             if (this.getZoom() > 8) {                 // Setup single tiled layer                 var untiled = new OpenLayers.Layer.WMS("cite:ly_parc - Untiled", "http://localhost:8082/geoserver/cite/wms",                      {                         LAYERS: 'cite:ly_parc',                         STYLES: '',                         format: 'image/png',                         transparent: true                     },                      {                         maxExtent: bounds,                         isBaseLayer: false                     }                 );                      this.addLayers([untiled]);             } else {                 //TODO             }         }     });


title: Does QGIS read NAS data?

text: I wonder if it is possible to load German NAS-Data into QGis or to convert them to Shapefiles. I'm using QGIS 1.8 on Ubuntu 12.04. Thanks * * * I'm sorry, I thought I did - NAS is the new Geodata-format, based on ALKIS- Data: http://de.wikipedia.org/wiki/Normbasierte_Austauschschnittstelle I installed the current Master on my Ubuntu 12.04 machine today and typed "ogr2org --formats" but NAS didn't appear on the list. If I check my ogr-version it says 1.7.3 - as I understood NAS is supported from 1.8.0 onwards. Did you do anything special to install that version? Thanks again


title: Unsplit lines seperated by a small gap

text: I have a set of polylines that represent fire hydrant laterals and many/all of them are in two peices one from the main to a valve on that line and one from the valve to the hydrant. Some have small gaps at where the valve is located which causes them to not unsplit when I run that command. I know functions like intersect have a search radius, is there something similar to this for the unsplit lines tool? Is there another way to do this?


title: Creating a layer switch Google Maps Api v3

text: I have generated a basic webpage with Visual Studio 2012 that displays a Google Map. My goal is to add multiple KML layers from my Server onto the Google Map, BUT, i want to be able to have a sort of switch that you can turn each file off and on, So my fist question is how can i add multiple layers from my server (I already know how to load 1) and how do i create this 'Switch'. I am using Visual studio 2012, Google Maps JS Api V3, and this is the current script:![enter image description here](http://i.stack.imgur.com/2nQSA.png)


title: shp2pgql: how to omit the git column?

text: I am importing a series of shapefiles with `shp2pqsql` that already have a unique identifier attribute. Since `shp2pqsql` creates a new column called `gid` I am ending up with two unique identifiers per record. Is there any way to tell `shp2pqsql` to omit the creation of the `gid` column? Or better still, to use the existing identifying attribute instead ? **Update** : I have `shp2pqsql` version _2.1.2 (r12389)_ installed. I am using it like: `shp2pgsql Roads.shp roads > load_roads.sql`


title: Is there a Legend Limiter in QGIS?

text: Is there in QGIS a function or a plugin that works similar to Legend Limiter in ArcGIS? The attribute I want to show in my legend has many possible values, I want my legend to only show those values that are visible on my view in the print composer.


title: QGIS 2.0 have a Legend Limiter feature?

text: I found this old post (concerning QGIS 1.x) Is ther a Legend Limiter in QGIS? and was wondering whether this had been solved in QGIS 2.0. Is there a way of only showing the attributes in the legend that are visible on the map? It seems to me that this is not straightforward in ArcGIS either and I think it would make sense to impement this (in QGIS as I'm trying to use ArcGIS as little as possible). Imagine how useful it would be when you have a geology maps and you don't want to show hundreds of formation but only the few formations you can actually see in the map composer ...


title: qgis web client tooltip

text: I need to create a tooltip in qgis web client. I have a postgres-layer and I added a column 'tooltip', but the tooltip does not show. I inserted just plain text in the tooltip column (I also tried with html), but it doesn't work. But I get an error message in the dev-tool: in FeatureInfoDisplay.js (115): cannot call method 'getAttribute' of undefined Seems to me that the server cannot read what's in the column Can anybody tell me what to enter in the tooltip-column to make it work. Thanks Ingrid


title: Does shapely within function identify inner holes?

text: I have a series of shapefiles that include both polygons and multipolygons. I am using ogr to extract them in wkb, and them I am using shapely to check if a point fall inside a polygon (or a multipolygon). However, examining some of the polygons in wkb I realized that many of them have inner rings (i.e. I have a set of coordinates describing the first, outer polygon, and a set of coordinates describing the inner polygon/s). Does the shapely `within` function take care of this, I mean, does it return `True` only if a point falls in the area delimited by outer and inner polygons? And are the inner polygons always supposed to be holes? I am sorry, perhaps these are really dumb questions, but I am completely new to this kind of analyses and, despite my efforts, I could not find some clear information about these doubts. Thanks in advance for your help.


title: Change color and format of scaleline

text: How can I change the format of the scaleline in OpenLayers? I have a black background and I want to change the lines in the scalebar to white. I use: `<link rel="stylesheet" href="http://www.openlayers.org/dev/theme/default/style.css" type="text/css" /> <style type="text/css"> div.olControlScaleLine{ color: white;   }` But this only change the font. Anybody kmow how?


title: How to remove sandy dots in an image?

text: ![portion of an image, need to remove pixels inside the ring and get pure brown color](http://i.stack.imgur.com/iS4qN.jpg) I am processing a LandSAT image for geological purposes. After some processing there are so many sandy dots in the image. To get clear geological formation as a polygon I want to remove small sandy pixels. After 'majority' filter, by 3x3, 5x5, 9x9 many of them still remaining. If you have any better idea for how to remove them the sandy, please share!


title: Exporting SHP files into Autocad readeable files

text: I have a full water supply network drawn in a shapefile which I created using Qgis 2.2.0. Now I need to export it into a format that enables me to open it in AutoCAD. I am trying to export it as a dxf file, but when I upload it in AutoCAD it shows an empty drawing (although the dxf file is 1.75MB). The shapefile is a line shapefile with several lines with a different main attribute (the diameter). Maybe I have to save different dxf for each diameter? Thank you in advance for your help.


title: How to load color attribute from shapefile in MapServer 5.0.x?

text: according to the docs of mapserver 6.0.x it is possible to load the color of a polygon shape from the shapefile. This is a great feature cos otherwise we would have to define a class for each different colored shape. But when I create the following mapfile and read it with mapserver 5.0.4, I get a               [MapServer Error]: getSymbol(): Parsing error near (SHAPE_COLOR):(line 1192)      The class in my mapfile is:               CLASS #default coloring         OUTLINECOLOR 0 255 0         COLOR [SHAPE_COLOR]     END      What is the proper syntax?


title: Error When Generating INSERT Statements for Geometry Field SQL Server

text: I am populating a column of linestrings from a list of points in sql with which I use to create insert statements to populate an ID and a geometry field in a table. This creates a temporary dataset using "with as" clauses, resulting in something like this: CLEAN_WKT               ID  WKT_LINE     1   'LINESTRING(56.750011 -168.150044, 56.833377 -168.083310)'     2   'LINESTRING(54.766722 -165.050055, 54.766788 -165.083311)'     3   'LINESTRING(56.683333 -170.066766, 56.866799 -170.300012)'             INSERT INTO TEMP(ID, GEOM)          SELECT ID, geometry::STGeomFromText(WKT_LINE, 0) FROM CLEAN_WKT;      This returns the error: The label 'LINESTRING(56.75000 in the input well-known text (WKT) is not valid. I can confirm that the linestring is created correctly, since I am able to print the resulting statement and execute it successfully. Resulting SQL statement:               geometry::STGeomFromText('LINESTRING(56.750011 -168.150022, 56.833333 -168.083322)',0)      Manually created insert statement from generated SQL (see above).               INSERT INTO TEMP(ID, GEOM)     SELECT '1',geometry::STGeomFromText('LINESTRING(56.750011 -168.150022, 56.833333 -168.083322)', 0);      Anybody know what the problem might be?


title: Is population density considered continuous data and why?

text: Population counts are typically referred to as discrete or quantitative data. Why is population density a continuous data type when it is typically measured for aggregate areas such as census tracts or districts/neighbourhoods (ie, it can't be measured at any point on a surface like gradient or temperature).


title: QGIS GDALtools plugin problem

text: I am trying to use the GDAL merge tool and receive the following error message: > The process failed to start. Either the invoked program is missing, or you > may have insufficient permissions to invoke the program. On install I checked the "Path to the GDAL Executables" and it already had the /usr/bin added to the install. Here is what I have in this field: > /Library/Frameworks/GDAL.framework/Versions/1.9/Programs/usr/bin Thanks in advance for any help with this issue


title: What's the centerline of a peninsula?

text: Given a peninsula stretching north south and the two coast lines connecting in the south, I want to find out which is the place, or rather line, which is furthest away from both coastlines on the peninsula? What I am looking for is the red line in the below image. The black and pink lines are the eastern and western coastlines. ![enter image description here](http://i.stack.imgur.com/0S4jW.png) One way could be to generate a polygon and do a negative buffer. An other one could be to add the longitudinal values, and divide by two. The latter one seems more rational - still it demands some programming and coordinate handling. But perhaps there is a third way? Any suggestions? ArcGIS and QGIS are both relevant tools of the trade here.


title: Obtaining average value around polygon in raster for different cross sections?

text: I have elevation data in a raster, river (blue line) and the flooded area (black polygon) as shown in the image below: ![enter image description here](http://i.stack.imgur.com/vuq7I.jpg) I want to find the water depth in the flooded area (inside the black polygon). Outside of the polygon, water depth is obviously zero. Inside the polygon, the land elevation is lower than outside (At least it should be) What I tried to do and did NOT work was this: I assigned nodata value to the points inside the polygon. Then I used Eucilidean Allocation to find the closest points just outside the polygon and assign it to nodata points. Then, I Subtracted the original land elevation raster from this new raster. However, I get big negative values because after all, it was not a good method at all. Now, I am thinking: I need to follow the water stream line. At each point, draw a perpendicular line to the river and let it intersect minimum two times with the polygon. Find the average value of cells inside a circle (with those intersections as center). Find the mean of these averages. apply this value too all points in that cross section (perpendicular line to the river). Now, is there any way on earth I can do this? Hopefully I don't need a for loop for this? Do you guys have any other suggestions, perhaps easier ways? I am using ArcGIS 10.1 with Spatial Analyst and 3D Analyst extensions.


title: Label changing with time slider using arcGIS

text: I have a list of lat/long locations with a time associated with them. With those locations I did a spatial join to find the total amount of points in each polygon. I would want to do is gradually increase the join count as the time slider advances. Is this possible in arcGIS? I have tried using the time slider the date directly, but the polygons would all disappear until a certain time is reached where all the points show up. EDIT: There are a set of dots that has a lat/long with a time associated with them on when they were created. Because I wanted to see how many of these dots were in each polygon, I used the spatial join tool and used the join count in that to determine the amount of points I have in each polygon. This join count would be from all the data that I have. What I want to do is to involve the time slider in this. For example, near the beginning of the slider, there would not be many join counts as the time has not happened. As I move the slider forward, each polygon would increase its join count as the points have reached their time.


title: How can data of columns of the attribute table be refreshed automatically?

text: I can't find a solution for an auto-refreshment of attribute table data. F. e. does the data of a shapefile-object (f. e. field calculator - $area) not change, if the geometry of the object is changed. Thanks for your help!


title: How do I convert a .bil (and associated .clr, .blw, .hdr, and .stx) files into georeferenced rasters in R? OR to geotiffs using gdal_translate?

text: The title says it all. I've got a bunch of .bil files, which I can open in R using the `raster` command pointed to the path to the .bil file. But I don't know how to efficiently incorporate the contents of the other files, which seem to be metadata, into the raster layer in order to georeference it. Alternatively, could I convert these sets of files to geotiffs using a `system()` call to `gdal_translate`? What would be the syntax for that?


title: How can I use Natural Earth's country data in TileMill without map tearing?

text: I am trying to import the ne_10m_admin_0_countries shp file from Natural Earth into TileMill but I get strange map tearing around Antarctica. I tried through PostGIS first (my main motivation for using this dataset) but later experimented and just tried to import the shp file directly with the same result. Does anyone have an idea what is going on and how to fix it? This is with TileMills default country layer: ![TileMill default layer](http://i.stack.imgur.com/vfm2S.png) With the ne_10m_admin_0_countries shp file: ![Natural Earth Data](http://i.stack.imgur.com/dWD6p.png) and with both of the layers showing: ![Both layers visible](http://i.stack.imgur.com/3nbTG.png) * * * (edit from comments below) The data looks fine in QGIS: ![QGIS vector layer](http://i.stack.imgur.com/GPmcb.png) * * * (2nd edit) It seems to come down to the following 2 points on Antarctica, but I am unsure how to fix it. I've increased the line-width to make the problem more clear. Northern / left problem point (zoom 10): ![northern / left](http://i.stack.imgur.com/wmAY1.png) Southern / right problem point (zoom 10): ![southern / right](http://i.stack.imgur.com/rxUXq.png) * * * (3rd edit) Okay so I tried reprojecting it from QGIS which just lead to QGIS crashing when I tried to save the shape file. I was trying to reproject it into EPSG:3857 / 900913: ` +proj=merc +a=6378137 +b=6378137 +lat_ts=0.0 +lon_0=0.0 +x_0=0.0 +y_0=0.0 +k=1.0 +units=m +nadgrids=@null +wktext +no_defs +over ` However I was able to get QGIS to do on the fly reprojection to EPSG:3857 and that also looks a bit strange: ![QGIS on the fly projection](http://i.stack.imgur.com/EQzFK.png)


title: Empty signature file after i.gensig in Grass (SOLVED)

text: I'm trying to make a supervised classification in Grass 6.4.3 under Linuxmint 16. After digitizing the training areas, I transformed them from vector to raster. Then I've done the following: just in case: `g.region rast=train_area_2013_03_05_raster@PERMANENT,2013_03_05_toar4@PERMANENT` then `i.group group=group subgroup=sub_group input=2013_03_05_toar4@PERMANENT,2013_03_05_toar5@PERMANENT,2013_03_05_toar3@PERMANENT` and `i.gensig trainingmap=train_area_2013_03_05_raster@PERMANENT group=group@PERMANENT subgroup=sub_group signaturefile=superv_class` but the resulting signature file, only contains one character: "#". The output of i.gensig in the console is the following:               Finding training classes...     3 classes found     Calculating class means...     Calculating class covariance matrices...     Signature 1 not invertible     Signature 2 not invertible     Signature 3 not invertible     i.gensig complete.      Obviously if I try: `i.maxlik group=group@PERMANENT subgroup=sub_group sigfile=superv_class class=results_class` I obtain the following error message: `ERROR: Unable to read signature file <superv_class>` I've been searching, but I couldn't find the solution. I've tried: this Problem running i.gensigset in Grass. Any ideas? My problem is similar to this: i.maxlik cannot read i.class output signature file. But here, there's no solution suggested. As in this case, I also used `i.cluster` to generate an unsupervised signature file and `i.maxlik` reads this perfectly well. Here there's another similar question, but again, with no solution... What does `Signature X not invertible` means? Any idea? Thanks for your help!


title: Recommend text for Spatial Analyst? (ArcGIS)

text: Does anyone have a recommendation for a good reference/tutorial(s) on Spatial Analyst? The most recent I can find are from early to mid 2000s. Or has SA simply not changed much in 7 years? Thanks, appreciate it.


title: Overview of SLD expressions

text: Does anyone have an overview of how expressions are supposed to work along with an overview of all available expressions. I have looked at the official references at the website of the OGC and I can find examples of how to use expressions but I have failed to find an overview of all expressions along with implementation details. To clarify what I am looking for, say I got a TextSymbolizer and I specify the Label element as:               <Label>         <ogc:PropertyName>road_name</ogc:PropertyName>     </Label>      What I would be looking for is: how should the expression be interpreted and what should it do when the property is not found. This is just an example and I am really looking for such information for all available expressions.


title: How do I bypass class extensions when reading from ArcSDE with FME 2014?

text: I'm trying to read Feature Class from our Enterprise Geodatabase and because we have custom class extensions registered on all our our data. I am not able to set the Reader to bypass the class extensions. I get this warning in the log "Unable to read from the table/feature class 'YK_SPATIAL.Buildings'. If 'YK_SPATIAL.Buildings' contains a class extension, make sure it is registered on this computer" Thanks


title: Lat/Lon/Alt to spherical or cartesian coordinates

text: On my previous question, it was advised I convert lat/lon/altitude to spherical or Cartesian coordinates. I'm not working near the poles and it would be safe to assume a spherical earth. What would be the best way to go about this with the minimal amount of operations? Would it be best to use x/y/z or phi/theta/rho? I'm working on a small microcontroller, with no hardware FPU (software FPU only!) so every cycle counts.


title: Find the best path along raster

text: I've just posted a question to StackOverflow about the best way to go about finding the best path on the raster below (where whiter pixels are 'better'), but have realised that it might actually be very easy to solve using some inbuilt GIS functions. To clarify, I'm trying to choose the best path down each of the lines shown in the image, staying on the bright white pixels as much as possible. ![RasterGridExample](http://i.stack.imgur.com/VbxRa.png) I have a feeling that the idea of Cost Surfaces and Cost Paths might help me with this, but I've had a play in ArcGIS and can't seem to get anything sensible out of it. Is this the right approach to take within a GIS? If not, are there some other inbuilt functions in a GIS that can do this kind of thing?


title: how do I reestablish all feature class references in mxd after their names change?

text: I have 200 shape files which have been named using an integer at the beginning of the name...i.e 01.03.shp 01.04.shp etc. They are all symbolized within an mxd document. I need to import these shapes into a file-GDB which is not permitted due to the fact that the feature class starts with a number - I can iterate through the shapes and rename them using a prefix, but then i´ll need to change the mxd reference for every single feature class because the names are different. Is there a clever way to get around having to fix every single reference in the mxd?


title: does Pseudo Mercator Projection causes problem while clipping rasters

text: I tryed to clip a Raster file using an ESRI shapefile using gdalwarp command, but i always get an empty output file or a wrong clip with wrong location. this the command bellow:               gdalwarp -dstnodata -999 -q -s_srs '+proj=merc +lon_0=0 +k=1 +x_0=0 +y_0=0 +a=6378137 +b=6378137 +units=m +no_defs' -t_srs 'EPSG:3857' -cutline mask.shp -crop_to_cutline -of GTiff inputRaster.tif outputRaster.tif


title: Good introduction to INSPIRE?

text: Can anyone point me to a good introduction to the INSPIRE directive? I know it's basically WMS 1.3 with added bells and whistles but now I'm back in Europe I should probably find out what they are.


title: How to select and highlight feature by attribute

text: I have the below code which does a select by shape on my arc map how do I achieve this with attributes 1.The map has only one layer 2.There is a filter for the attributes on features Below is the Code                 private void ZoomToDGVSelection(int selectedRightID)         {                  IMxDocument pMxDoc = ArcMap.Document;             IMap pMap = (IMap)pMxDoc.ActiveView;                  ESRI.ArcGIS.Carto.ILayer layer = GetLayersClass.GetFieldBoundaryLayer;             if (layer is ESRI.ArcGIS.Carto.IGroupLayer)             {                                ESRI.ArcGIS.Carto.IGroupLayer groupLayer = layer as ESRI.ArcGIS.Carto.IGroupLayer;                 ICompositeLayer pCompositeLayer = layer as ICompositeLayer;                 int layers = pCompositeLayer.Count;                 ILayer pLayer = pCompositeLayer.Layer[0];                 IFeatureLayer pFeatureLayer = (IFeatureLayer)pLayer;                      IFeatureClass pFeatureClass = pFeatureLayer.FeatureClass;                 IQueryFilter pFilter = new QueryFilterClass();                 pFilter.WhereClause = "RightID = " + selectedRightID.ToString();                      IFeatureCursor pFeatureCursor = pFeatureClass.Search(pFilter, false);                 IFeature pFeature = pFeatureCursor.NextFeature();                      if (pFeature == null)                 {                     System.Windows.Forms.MessageBox.Show("This section doesn't exist");                     return;                 }                           pMap.SelectFeature(pFeatureLayer, pFeature);                 IEnvelope pEnv = pFeature.Extent;                 IGeometry pgeom = (IGeometry)pFeature.Shape;                 pMap.SelectByShape(pgeom, null, false);                 pMxDoc.ActiveView.Extent = pEnv;                 pMxDoc.ActiveView.Refresh();             }         }      Thank you in advance.


title: Selecting polygons by number of sides

text: I'm using ArcGIS 10 to build some figures for a journal article. One is a figure of an unstructured finite element mesh of triangles spanning the western Atlantic Ocean. I exported this mesh from SMS to a polygon shapefile where each triangle is a polygon and added it to my ArcGIS map. It looks great; however, the islands (such as Haiti and Cuba) are also polygons in the shapefile. I would like to remove them without manually selecting them all. **Is there a way I can select only the polygons with more than 3 sides in order to delete them?**


title: How to install ArcGIS Desktop 9.3 on Windows 8 (64 bit)?

text: I have installed Arc GIS 9.3 on window 8, 64 bit but the lisence server says not valid license server or the older version is running how can I solve such like problems?


title: Image Service Descriptions

text: When you load an image service to ArcServer, you have the option to place an Item Description with the service. This acts as the metadata, however it displays a duplicate: "Service Description" then right below it "Description" The information is an exact replication.![enter image description here](http://i.stack.imgur.com/31C4y.png) When you edit the Item Description of the mosaic dataset and restart the service, both Description blocks update. How do I edit/remove one of the Description blocks to avoid redundancy? ![enter image description here](http://i.stack.imgur.com/97oAz.png)


title: ESRI android SDK Calculate area in square meters from polygon geometry

text: Hello I have a Polygon object in ESRI Android SDK that I'm creating on a map, I would like to calculate that polygon object to square meters. currently I use                double area=polygon.calculateArea2D();      But I don't know what that geometry's default unit is to convert from.. Anyone know how I can take that Geometry's area and convert to meters squared? thanks!


title: Calculate text field based on codeblock query of numeric field

text: I am trying to populate a field with a L/R bank designation based on a route measure (as part of a larger script), but I am struggling. I have a shapefile created ( _tir_pts_lyr_ ), I have a blank column ( _L_R_Bank_ ), I have the measure value column ( _M_off_str_ ). So if the measure value is negative, I want "L_R_Bank" to be populated with an "L", if the measure is positive, an "R", and if zero, a "C".   I'm trying to use the sample codeblocks in the ArcHelp, but they are lacking in detail for my knowledge level. I have no clue what to put in the expression field for getClass and how the next codeblock line relates to that. Any hints for a newbie.               #calc left/right bank using M-distance measure     # Set local variables     inTable = "tir_pts_lyr"     fieldName = "L_R_Bank"     expression = "getClass(float(!SHAPE.M_Off_str!))"     codeblock = """def getClass(M_Off_str):         if M_Off_str < 0:             return "L"         if M_Off_str > 0:             return "R"         else:             return "C" """     #Execute CalculateField     arcpy.CalculateField_management(inTable, fieldName, expression, "PYTHON", codeblock)


title: How to calculate Bearing between two GPS points

text: The following returns 150 degrees using C# converted from JavaScript Bearing formulas, but Google earth returns 210 degrees for the same values. The broken code is GetBearing() but I've also included Calculate() to show hard coded test values and ParseCoordinate() to show that I am converting Degree-Minute- Second to radian decimal degrees for GetBearing(). Are the JavaScript Bearing formulas wrong?               double DEG_PER_RAD = (180.0/Math.PI);     // Return Bearing (degrees)     private double GetBearing(double lat1, double lon1, double lat2, double lon2)     {         var dLon = lon2 - lon1;         var y = Math.Sin(dLon) * Math.Cos(lat2);         var x = Math.Cos(lat1)*Math.Sin(lat2)-Math.Sin(lat1)*Math.Cos(lat2)*Math.Cos(dLon);         return DEG_PER_RAD*Math.Atan2(y, x);     }     private void Calculate()     {         var lon1 = ParseCoordinate("38 51 30.5");         var lat1 = ParseCoordinate("78 12 33.8");         var lon2 = ParseCoordinate("38 45 46.2");         var lat2 = ParseCoordinate("78 16 46.0");         var bearing = GetBearing(lat1, lon1, lat2, lon2);         // Show bearing         ...     }     // Convert Degree-Minute-Second to Degree.ddd     private double ParseCoordinate(string coordinate)     {         var dms = coordinate.Split(' ');         var rVal = 0.0;         var i = 0;         foreach (var s in dms)         {             double d;             double.TryParse(s, out d);             rVal += (d/(Math.Pow(60.0, i++)));         }         rVal /= DEG_PER_RAD;         return rVal;     }


title: Correct way to zoom on php mapscript. Zoom not center

text: I have a 800x600 pixel map image generated with php mapscript. Whenever i want to zoom to a certain point on the map, it doesn't centerly zoom to that point. I use the zoompoint() method. The x and y value is from the coordinate where user click on the map image file. Any idea ? Thanks. :)


title: Can't find the toolbar for sorting the table of contents in alphabetical order in Arcmap!

text: I am using ArcGIS Desctop 10.0 Service Pack3 and I'd like to sort the table of contents in alphabetical order but following Sorting the table of contents in alphabetical order I can't find the "Production TOC Manager" toolbar. Am I missing anything or do I need to activate anything?


title: DotSpatial: Convert a Polygon Feature to System.Drwing.Region

text: I want to paint a Polygon region with a color. I know I can use `Symbolizer` to do this but I want that region to blink (change it's color in a timer) and using `symbolizer` seems to be slow for this purpose. I'm already using `Map.OnPaint` event to draw a colored image of a point (in a `PointLayer`). So how can I Convert a Polygon Feature (in a `PolygonLayer`) to `System.Drwing.Region` so I can use methods in Graphics class to paint that region? Thanks in advance.


title: automate color palette generation?

text: I frequently am in need of color gradients that aren't readily available through ArcGIS or the ColorBrewer add-in. I find the process of manually creating gradients in Arc very tedious: saved custom colors don't come up in the edit color ramp window. I am wishing that there was some way to use Python to batch generate colors ramps for ArcGIS. For example, if I gave it a "high" color and a "low" color, it could create and import a linear gradient between the colors. Importing might simply be a matter of saving to a specified directory.


title: How can I do a batch edit of circle diameters using the attribute table in ArcGIS?

text: I need to edit the diameter of a bunch of circles to reflect their correct diameters, and I wondered if there was a way of drawing from the attribute table to make all the circles equal their correct diameters rather than redrawing all the circles with the correct diameters by hand. Thanks!


title: Why does the map take so long to display and appear distorted?

text: I have map rendered from geoserver but it takes too much time, again shown map is half-shown and distorted as the following image, **SOMETIMES THE MAP DOES NOT EVEN DISPLAY** ![my distorted map in open-layer](http://i.stack.imgur.com/V9QWQ.png) My JAI setting is as below               <jai>         <allowInterpolation>false</allowInterpolation>         <recycling>false</recycling>         <tilePriority>5</tilePriority>         <tileThreads>7</tileThreads>         <memoryCapacity>0.5</memoryCapacity>         <memoryThreshold>0.75</memoryThreshold>         <imageIOCache>1</imageIOCache>         <pngAcceleration>true</pngAcceleration>         <jpegAcceleration>true</jpegAcceleration>         <allowNativeMosaic>false</allowNativeMosaic>     </jai>      URL IS               http://localhost:8080/geoserver/it.geosolutions/wms?service=WMS&version=1.1.0&request=GetMap&layers=it.geosolutions:thanaboundary&styles=&bbox=88.1099243164063,21.1824684143066,92.5484466552734,26.4899482727051&width=428&height=512&srs=EPSG:4326&format=application/openlayers      My PostGIS DataBase Content in SQL is as below                 -- Table: thana            -- DROP TABLE thana;            CREATE TABLE thana       (             gid serial NOT NULL,             objectid integer,             recid numeric,             geocode numeric,             div_code numeric,             div_name character varying(254),             dist_code numeric,             dist_name character varying(254),             thana_name character varying(254),             thana_code numeric,             shape_leng numeric,             shape_area numeric,             noofbed double precision,             bedoccupen double precision,             dailyavgop double precision,             geom geometry(MultiPolygon,4326),             CONSTRAINT thana_pkey PRIMARY KEY (gid)       )      WITH (            OIDS=FALSE           );            ALTER TABLE thana            OWNER TO postgres;            -- Index: thana_geom_gist            -- DROP INDEX thana_geom_gist;                    CREATE INDEX thana_geom_gist               ON thana               USING gist               (geom);      My geoserver web page ![enter image description here](http://i.stack.imgur.com/lEFvw.png) Would any one with any tweak please


title: How could I crowdsource spatial data with online clickable map?

text: Here in northern Tanzania we are experiencing a huge westward butterfly migration \- originally those of us who saw it thought it was local but it turns out that it's very widespread. We're getting informal reports from all over, but would like to (quickly!) set up a way for people to report sightings:   * A clickable map on a web page that lets people show the location of a sighting;   * A form that collects some other basic data;   * Logging of spatial points and the form data. Ideally this could be done through a Facebook page as social media will spread this like ... well, like a butterfly migration in a high wind ;). Any ideas? Update: here's the Google Map showing sightings.


title: How to create a service area using both streets and buslines in the same network?

text: I want to create a network analysis more difficult. Therefore, I want to calculate a Service Area around hospitals next to busstops. But: The network does not only consist of roads and pedestrians(time) but also of buslines and busstops. In best case the result should be a augmented service area, which includes bus drives to the hospital in a certain time! I nearly have the solution, but here is the problem. Trying to solve the analyse I realized that serveral busstops are not within the calculation. I have checked the topology of the stops and lines and there are no errors (as arcgis says). Also the attribute table seems to be correct. I tried to planarize the bus lines but I cant use the tool, as it is not possible to click on it (grey color). Maybe you have a idea to help me? Thanks a lot in advance! Problem picture: ![enter image description here](http://i.stack.imgur.com/xTZKd.jpg) (Source)


Is there a way to manually place labels in QGIS? I have a map which has almost-duplicate labels in some places (e.g. E 1st St and 1st St) and I'd like to remove some of them. Also, I'd like to move some of the labels around and maybe label some features that aren't currently. I'm using new labeling, with the labels curved along the features.


title: How to determine if a raster has rowattributes?

text: I have a raster file which is the result of extract by mask geoprocessing tool. If it has no rows then I take it as no overlap between input raster and shapefile. Following is the way I am reading it to determine whether a row exists or not. But it gives me zero answer even if a row exists. Please help me to better control this process.                   a = 0         grid1 = arcpy.sa.ExtractByMask("iras",fc)         grid1.save(optfolder + '/oras')         arcpy.BuildRasterAttributeTable_management(optfolder + '/oras',"Overwrite")         grid2 = arcpy.SearchCursor(optfolder + '/oras',"","","Count","")         rows = grid2.next()         if rows == None:             count = 0             a = a + count         else:             count = rows.getValue("Count")             a = a + count              del rows


title: DC-GIS WMS server. Metadata shows polygon layer, why am I getting a raster

text: This page gives the description of the layers available from the DC_GIS mapserver. When I look up the metadata for various layers, say record lots, the description says   Geometry Type: esriGeometryPolygon   but when I fetch the layer using either qgis or ArcMap, I get a raster layer. I've tried this for several different layers which describe themselves a polygons, but always get a raster. In ArcMap I download the .lyr file. In qgis, I copy the WMS URL, open it in the New WMS servers dialog and select the layer to add. Is it me or is it the metadata?


title: ArcSDE - Creating new install on new database with existing SDE schema

text: I asked a question before, but was probably not specific enough, so didn't get the information I required. My fault completely. I am creating a new sde instance on a server. This needs to be pointed at an existing Oracle 11g database, that has a pre exisiting SDE schema and data in it. Now all the installs I have seen, have created all of the system tables, but this one doesn't need to, as they are there. Also, which is more alarming, is that I cannot perform an upgrade, as it hasn't been installed before. Not too sure how to take it from here. I don't normally work with SDE, buit have thoroughly researched the issue. Has anyone seen this issue, or have advice as regards the issue? Thanks in advance. **EDIT** This is my plan of action.   * Dump file of Oracle non spatial data   * Install SDE   * Create new Schema   * export SDE data from old DB (sdeexport)   * import SDE data from sdeexport file We'll see how that fares, but it appears the only way to me.


title: Calculating Distances between Field polygons via Road polygons using ArcGIS for Desktop?

text: ![Two layers, both polygons](http://i.stack.imgur.com/BO0tz.png) I have two polygons layers, one (grey) is Roads, other (blue) is Fields. Can I calculate distances between Fields (by field unique ID number) using Roads layer as distance measurement? What tools or extensions should I use?


title: QGIS Select Single Feature not correct in attribute table

text: For some reason, QGIS is not displaying the correct row of my data when I click on a feature with "Select Single Feature" or even the other select tools. I have a point database linked from mysql. There is a column named ASR with a unique number. When I plot all of the points, they are correct - everything is where it should be. When I label the points they are all correct - ASRs correspond to points in the correct locations. When I open the attribute table, select a line, and then zoom to that feature, it works fine. Correct point, correct labeling, all good. HOWEVER, if I just display the map of all the features and try clicking on one with the 'Show selected only' checked, it doesn't actually select the right point, and moreover it shows the wrong row. In most cases if I select a rectangle of 20 or 30 points, it actually highlights 20 or 30 OTHER points, and displays various results in the attribute table. I'm totally confused. Almost everything is working right and its clear that the record data and point data are correct and in agreement, but selecting features by mouse is totally hosed. Any ideas?


title: Getting Layer in WMS and Editing in WFS-T on OpenLayers

text: **I have huge datasets on PostGIS**. For example building table includes more than **100k features in POLYGON geometry**. When i want to get all data in QGIS(2.1) or other GIS softwares by using direct **DB connection i wait about 30 sec**. But if use **WFS connection** (Geoserver) it takes more time (dont try)... **In a webgis project** (using openlayers) people down want to wait in front of the screen. And I think **Openlayers cant handle with that huge data**... So i use to serve data by **using WMS**. Its really to fast and maybe later i try tilecaching etc... Ok everything is so far so good. But **I want to edit features** ( **only insert** maybe delete no update) on the browser. I have cheched Openlayers examples for **WFS-T**. These examples load all data to by WFS. **I dont want loading data just inserting new features by drawing and than clicking save button.** So new features sending to geoserver... I tried with Openlayers WFS-transaction example link. Firstly modified data `map.addlayers([wfs,gpyh]);` to `map.addlayers([gpyh]);` to load only googlemaps baselayer. There is no error during drawing but when saving i get error. I says               this.layer.map is null            var local = this.layer.map.getProjectionObject();      What do you advise me when working with big layers.Is my way corretc. How can i handle with this issue? My javascript knowledge is limitied. **EDIT** Some info about the system which i want to build: **I want to serve buildings, roads, boundary etc. layers to people. Not only showing but also editing capabilities it should have.** **MY PROBLEM:** I dont want to load features to OpenLayers, i just want to draw new features and put them into database. And I use WMS for serving layers. I use OpenLayers lib in client side (apprentice in javascript). The data is stored in Postgis. But i can use Spatialite. Geoserver for WMS and WFS service. I am not bad in Python and PHP. Maybe i can use FeatureServer. Also i can serve feature data with PHP or Python.


title: Issue with Sextante r.map calculator and modeler

text: I am trying to build a model with Sextante modeler and the r.mapcalculator algorithm but when I run the model I get the error message:               ‘Could not load layer: ‘….’Check sextant log to look for errors in algorithm execution.’      The Sextant Log reads:               sextante.runalg("modeler:ndsi.","H:/NDSI/MODIS/20120607_SurfaceReflectance        /0607_Processed Images/0607_b4_warp","H:/NDSI/MODIS/20120607_SurfaceReflectance           /0607_Processed Images/0607_band6_warp","H:/NDSI/MODIS/test/NDSI")      The algorithm I have put into r.mapcalculator is a basic algorithm to calculate NDSI for snowcover analysis:               e.g. (amap-bmap)/(amap+bmap)          amap = band 4          bmap= band 6      I have tried on different computers as well as only using the r.mapcalculator through the Sextante Toolbox. Is there a different calculator I can use in my model? Is there a different way I should write out my algorithm?


title: automating roof orientation detection from satellite imagery

text: A while ago I did a neighbourhood roof orientation survey for solar panel deployment, by visually checking each roof and marking individually whether they were south or almost south-facing. As this is very time-consuming, I would like to find a way to automate this, but don't know how this would be possible by merely analysing roof shadows. I can script a little but have never written any plug-ins. What other elements do I need to include? We are on a very low budget, so any suggestions how to do this using open source tools would be welcome. Thanks!


title: How can we protect GIS data?

text: I have found a very interesting paper here related to this topic. I just want to have views/ideas from other professional about how we can protect GIS data using Cryptography or Digital Watermarking? Any suggestions, especially for Administrative layers of a country where source of layers is same for every company so output is also same more or less. I am interested in some methods like one suggested here


title: Calculating the outer boundary of several Geometry objects in SQL Server 2008

text: I have lots of `Polygons` of datatype `Geometry` in SQL Server 2008. The image below shows how a select of all these Geometrys looks visualized. ![Lots of Geometrys](http://i.stack.imgur.com/720hk.png) What I need to do is create a Polygon which represents the outer boundary of all these polygons. So I used the response given to a previous spatial question I asked to create the following code:               DECLARE @test TABLE(geom GEOMETRY);          INSERT INTO @test SELECT geom FROM ForceBoundary          DECLARE @geom GEOMETRY     SELECT @geom = (SELECT TOP 1 geom FROM @test)     SELECT @geom = @geom.STUnion(geom) FROM @test          SELECT @geom      This produced the following result, which has _cracks_ in it due to holes between the polygons: ![Combined polygons with cracks](http://i.stack.imgur.com/vzlEu.png) So I updated my query with the following change:               INSERT INTO @test SELECT geom.Reduce(0.001).STBuffer(100) FROM ForceBoundary      Which improved the result, however it's not solving the issue completely and it also damages the outer boundary accuracy. ![Combined polygons with less cracks](http://i.stack.imgur.com/Wukle.png) **What is the correct way to achieve this?** From looking through a list of the STxxxx functions I couldn't see one that seemed to provide the results I need? I've tried `SELECT @geom.STExteriorRing()` but it doesn't return anything. Appending it with `.STAsText()` returns null.


title: Best software to draw lines on Maps (eg. Neighbourhoods or Streets) and then import it into SqlServer 2008?

text: I wish to draw some custom boundaries (eg. neighbourhoods or streets or city boundaries).   1. What software (free or paid) can I use to do this? I read that google maps recently has support for this?    2. Import this boundary into Sql Server 2008. Are there any links, tutorials or info anyone can provide, please?