title: purpose of maxExtent?

text: I am starting with maps but im a beginner. The answer is probably easy, but i could not find it anywhere. I cannot figure out why to use maxExtent. If I delete it from my application, its behavior doesn't change or I do not notice. So why should I use it? I understand purpose of restrictedExtent but not of maxExtent. Can you please somebody please explain it to me, thank you.               var extent = new OpenLayers.Bounds(-2003750.34, -2003750.34, 2003750.34, 2003750.34);          map = new OpenLayers.Map("map", {             controls: [                             new OpenLayers.Control.Navigation(),                             new OpenLayers.Control.PanZoomBar(),                             new OpenLayers.Control.ScaleLine(),                             new OpenLayers.Control.Attribution(),                             new OpenLayers.Control.LayerSwitcher()],             maxExtent: extent,             //restrictedExtent: extent,             maxResolution: 156543.0399,             numZoomLevels: 19,             units: 'm',             projection: new OpenLayers.Projection("EPSG:900913"),             displayProjection: new OpenLayers.Projection("EPSG:4326")         });          var osm = new OpenLayers.Layer.OSM.Mapnik("Mapnik", { 'attribution': 'Provided by blop' });     var gmap = new OpenLayers.Layer.Google("Google Streets", { visibility: false });          map.addLayers([osm, gmap]);


title: arcpy ArcGIS Server

text: Could someone please help me by giving me an example on how to make/connect/Add ArcGIS Server connection via python/arcpy? Thank you in advance.   * I'm using ArcMap 10.0   * I desire to "Use GIS Services" not "Manage GIS Services"   * My ArcGIS Server does not require Authentication When I make this connection through the wizard(steps previously described) all I have to provide is the Server URL and then navigate to my Image Service of choice. I've noticed there is a function in ArcMap 10.1 (CreateGISServerConnectionFile (arcpy.mapping)) which all allows me to make a Arc GIS server connection but not for ArcMap 10.


title: How to Exclude Processes from Iteration in ModelBuilder?

text: Is it possible to break Iterate Raster after certain set of processes ? I have a list of Image files which I am processing using Iterate Rasters and performing aggregate and Extract Values to Points and then writing the output to a textfile. I have three processes:   1. Aggregate   2. Extract Values to Points   3. Writing to textfile I want to execute process 1 and 2 in Iterate, but 3 Process I don't want to perform in the Iteration. Instead, I want to perform process 3 after all the Iteration got completed for the 1 and 2 process in the same Model. Anybody has any idea how can I achieve this in the same model?


title: Steps for creating an online webmap with editable features using ArcGIS Server/SDE and SQL Server?

text: EDIT/UPDATE: I'm adding a bounty to this in hopes of obtaining a step-by-step guide to creating an online map with **feature editing** using the ArcGIS Flex API, SQL Server **Express** and ArcGIS Server 10.1. I've run into so many issues (database authentication with Express, errors enabling feature editing) that I think my best bet is to start over and go through each step. A moderately detailed guide would be very much appreciated. * * * I'm primarily a desktop GIS programmer and need to develop a web application in which features can be edited by multiple users. I'm looking for a brief summary of the full steps I would need to carry this process out if I were starting from scratch. Software: ArcGIS Flex API and SQL Server Express with ArcGIS Server 10.1. The steps as I understand them so far: 1) Install ArcGIS Server on our server (actually a virtual machine on an existing server) 2) Install the ArcGIS Web Adapter 3) Install ArcSDE on the same server 4) Install SQL Server Express on the same server This is where I need some clarification. As I understand it I need to create a new geodatabase to store the features I wish to display/edit. I also understand I need to create a Feature Service and Geometry Service. Finally I will need to host the developed application using a web server. I'm essentially looking for a walk-through for this process as I have never carried it out before. Any information/resources would be much appreciated.


title: overpass-api or osmconvert: which method is more appropiate to use for files from 10 to 400 mb?

text: new to openstreetmap and this technology. **update:** some mentioned **postgis** : well - The database schema of postgis allready contains the following tables: nodes, ways, relations, node_tags, way_tags, relation_tags, way_nodes.... well - can i do imports into postgis - as easy as into mysql? i want to gather data from .o5m & pbf file - several ways are possible: what is wanted: i look for restaurants - with all of the following tags: [code]@id @lon @lat amenity name adress [as town, street, housnumber] website and mailadress. [/code] All interests are based on the regions of Germany see http://download.geofabrik.de/europe/germany.html i have several files i want to work with - ranging form 10 MB (Bremen) to 390 MB (Nordrhein Westfalen) the osm.pbf-files are not too big; **main question:** which method is the best and the most appropiate? - to store the results in a mysql-db or just have big calc-sheets (with csv-data) To achieve this goal of having only certain features in my csv file, we will have to filter the csv file generated by osmconvert afterwards. Also, the arguments to the --csv option of osmconvert are the tag keys we want to have in our csv file. If we want "amenity" and "name" columns in addition to id, lat and lon, we specify "@id @lon @lat amenity name", and then filter the CSV output. a. use osmconvert to convert osm to .o5m and .pbf file it works fine but am having problem converting osm to .csv or excel file **example:** I can use                ./osmconvert addis.osm --all-to-nodes --csv="@id @lon @lat amenity name" --out-csv -o=outfile.csv      and subsequently:               grep cafe outfile.csv > cafes.csv     grep restaurant outfile.csv > restaurants.csv     cat cafes.csv restaurants.csv > cafes_and_restaurants.csv      b. on the other hand i can do this way: **use overpass-api:**               <query type="node">       <has-kv k="place" v="city"/>       <has-kv k="name" v="any town "/>     </query>     <query type="node">       <around radius="1000"/>         <has-kv k="shop"/>     </query>     <print/>      **question** : are there more (effficient) ways!? i need to have the most efficient. b. - the overpass-api-method creates a XML-file (more or less large ) for example a XML file which I created from the overpass api. This i would need to load into a mysql database. btw: i use this to LOAD XML LOCAL INFILE '/home/jay/Downloads/interpreter1' into table jayDB.xml1 (id); I'm new to XML so not sure if this is possible.               <osm version="0.6" generator="Overpass API">     <note>     The data included in this document is from www.openstreetmap.org. The data is made available under ODbL.     </note>     <meta osm_base="2013-03-07T14:54:02Z" areas="2013-03-07T10:37:02Z"/>     <node id="240486180" lat="50.9744274" lon="3.0152858">     <tag k="addr:housenumber" v="9"/>     <tag k="addr:street" v="Marktplaats"/>     <tag k="amenity" v="cafe"/>     <tag k="email" v="vandaelekoen67@skynet.be"/>     <tag k="name" v="Paviljoentje"/>     <tag k="opening_hours" v="Mo-Su 09:00+; Tu off; Th 09:00-14:00"/>     <tag k="phone" v="+3251636211"/>     <tag k="website" v="http://www.paviljoentjestaden.be"/>     </node>     <node id="244312208" lat="51.2461401" lon="5.4390455">     <tag k="amenity" v="cafe"/>     <tag k="created_by" v="JOSM"/>     <tag k="name" v="De Club"/>     </node>      however i think due to the format of the file it thinks K and V are the columns. Where as I was amenity to be column and cafe to be the value i tried to look atthe details https://dev.mysql.com/doc/refman/5.5/en/load-xml.html **as mentioned above** : the main question: which method is the best and the most appropiate? - to store the results in a mysql-db or just have big calc- sheets (with csv-data) love to hear from you


title: Where can I find a shapefile of the Indian electricity grid?

text: Does anybody know where I can find a shapefile of the major components of the Indian electricity grid? Ideally, I'd get transmission/other high-voltage lines, substations, generating units, and transformers. I know there are power maps out there (like this one), but I want to match these transmission lines up with geographical data, so more precise locations would be helpful. Thanks!


title: What exactly is the min/max of an extent? (QGIS heatmap plugin)

text: I'm having a hard time making the heatmap plugin do precisely what I want (namely, to make a heatmap showing not only points but an attribute of those points), and now I'm thinking that I may be misunderstanding what "min/max of full extent" means. To my mind, the minimum and maximum values QGIS pulls out of the attribute field and displays in the band rendering section should be the lowest and highest numbers that appear in that column. Is that actually correct? (In that case, my max should be 6500 or so. Instead, it's 10.35.)


title: Why don't all the attributes in the SQL query appear in table?

text: I have an SQL query that works fine in the DB Manager but when I load the table as a layer one column does not get loaded. The different thing about this column is that it is static -- text generated with the query and the same for each row. It is actually a template for data entry that I want to print on the reverse side of the map. Effectively a check list for each item. The only way I could see to get it printed was to add it as an attribute to each row. eg.               <site name>  Vistited ( ), count1 (  ), count2 (  )....      so volunteers can check fill in the details and the photo


title: Hand-written coordinates from a Garmin NUVI

text: I've been asked to map point data that was collected in the field by manually writing down the coordinate from a Garmin NUVI 1490 LMT. They were put into a spreadsheet and sent my way which I was able to convert from DDM to DD in Excel. I've tried a bunch of different ways to import the points into ArcGIS using Add XY data with the same result (see attached image of street centerlines and points). The street centerine data is what I'm hoping they'll line up with (they're locations of street signs). At first I suspected the projections I was using but after much experimentation I think it may be the conversion formula I used (found here: http://www.ozgrid.com/forum/showthread.php?t=155776). Can anyone offer any advice as to where I've gone wrong and set me straignt?   ![enter image description here](http://i.stack.imgur.com/ytH7e.jpg)


title: ArcGIS ApplyEdits w/ JavaScript

text: I'm new to ArcGIS API. In a form, how can you submit data to modify a feature using applyEdits? No map is involved with this. I have a form that populates the editable data with javascript. When the user clicks save changes, I want the changes to be processed using applyEdits. So far, I have:               var Editable = new FeatureLayer("......", {             mode: FeatureLayer.MODE_SNAPSHOT         });              Editable.applyEdits(null,[ {           "attributes": {             "bldg_prop_id": 6086,             "bldg_water_utility_name": "New Data"           }         }],null);        This doesn't work but I'm not sure where to go with this.


title: Why does multi-threaded rendering not use all the CPU potential in QGIS 2.4?

text: I have just downloaded QGIS 2.4 which is great and ran some tests. I have enabled the multi-threaded rendering but it seems that the program do not use all the potential of my CPU. Attached pic shows CPU usage when QGIS is rendering (top) and some other multi-threaded program I am using. As You can see the "other" program takes all the cores to a 100% while QGIS only took half of them. The rendering time in this case was 78586 ms, so it's not like it couldn't be any faster. Max cores to use is set to 8. Is this normal or am I missing something? ![enter image description here](http://i.stack.imgur.com/cXFAP.png)


title: PyQGIS - QgsMapToolEmitPoint

text: I would like to make use of Signal and Slot while using PyQgis along with PyQt4. Despite spending some time trying out tutorials and some somewhat related post on gis.stackexchange I can't figure out a proper way of using the canvasClicked signal returned from the QgsMapToolEmitPoint Class (API doc). Here after is where I'm at. I am building my application from the few tutorials man can find over the internet.                   self.clickPoint_action = QAction(             QIcon(":/ourapp/zoomin_icon"),             "Click Point",             self)                   # create toolbar         self.toolbar.addAction(self.clickPoint_action)              # connect the tool         self.clickPoint_action.triggered.connect(self.clickPoint)                   # create the map tool(s)         self.tool_clickPoint = QgsMapToolEmitPoint(self.map_canvas)               def clickPoint(self):         self.map_canvas.setMapTool(self.tool_clickPoint)       So, I understand how to set my map tool (and successfuly use other built-in and custom MapTool), but can't figure out where to go from there to get the corresponding QgsPoint emitted after a mouse click. I have few experience on Python and just dive into Qt and PyGIS but already have some background mostly wth java. thanks for sharing!


title: MODIS MOD13Q1 ndvi calculation

text: i have downloaded the modis MOD13Q1 from usgs glovis in hdf format. how i will convert it into original ndvi value by multiplying scale factor of 0.0001. I am using ERDAS 9.1 & evni 4.7. Can you plz tell me the step by step procedure get the ndvi value.


title: After ArcGIS 10.2.1 update, Arcpy 64 bit import Error

text: I've updated my ArcGIS desktop version from 10.2 to 10.2.1 and have noticed that when I run the 64 bit version of IDLE I now get an error when trying to import arcpy:               Python 2.7.3 (default, Apr 10 2012, 23:24:47) [MSC v.1500 64 bit (AMD64)] on win32     Type "copyright", "credits" or "license()" for more information.     >>> import arcpy          Traceback (most recent call last):       File "<pyshell#0>", line 1, in <module>         import arcpy       File "C:\Program Files (x86)\ArcGIS\Desktop10.2\arcpy\arcpy\__init__.py", line 24, in <module>         from arcpy.toolbox import *       File "C:\Program Files (x86)\ArcGIS\Desktop10.2\arcpy\arcpy\toolbox.py", line 656, in <module>         from na import AddFieldToAnalysisLayer as AddFieldToAnalysisLayer_na       File "C:\Program Files (x86)\ArcGIS\Desktop10.2\arcpy\arcpy\na.py", line 26, in <module>         import _na       File "C:\Program Files (x86)\ArcGIS\Desktop10.2\arcpy\arcpy\_na.py", line 46, in <module>         class StreetDirectionsProperties(na.StreetDirectionsProperties):     AttributeError: 'module' object has no attribute 'StreetDirectionsProperties'      So the error seems to come from failing to find a module for the Network Analyst extension, which I see is listed as one of the updated Python features in 10.2.1: (http://resources.arcgis.com/en/help/main/10.2/#/What_s_new_in_ArcGIS_10_2_1/016w0000005v000000/). I'm guessing the 10.2.1 release didn't update both the 32 AND 64 bit versions of Arcpy when installing Python 2.7.5. The version I still have in C:\Python27\ArcGISx6410.2 is 2.7.3, but this seems to now be in conflict with the new install. Can someone please help me figure out how to correct this issue with IDLE? I really need to be able to run stand-alone 64 bit Arcpy scripts. I'm aware of 64 bit background geoprocessing in ArcMap/ArcCatalog, but this is different. I run heavy lifting stand-alone scripts that must be in the 64 bit version. Thank you


title: How to open a raw binary raster in QGIS or R

text: I have a raw binary raster without a file ending, and no header file. I would like to open this in either QGIS or R and then convert to geotiff, but opening it seems to be a challenge. Here is a link to an extract or part of the original image. https://dl.dropboxusercontent.com/u/17287323/test51by51_s1 The image has the following properties: nrows: 51 ncolumns: 51 datatype: 16 bit integer Number of bands: 1 pixel size is 231.656 x 231.656 m For the original image, I have the coordinates for the UL pixel, but not for this extract. Any help is greatly appreciated.


title: Error with Python Script tool for ArcGIS 10.2

text: I am trying to create an ArcGIS map tool that includes creating TINS and uses parameters. This tool works fine when taking the data from shapefiles, but when I use map layers, which is what I want it stops working at CreateTin tool with the error: Failed to execute (CreateTin). Here is the TIN creation code that I am using:               # Import arcpy module     import arcpy, sys, string     from arcpy import env     from sys import exit          # Check out any necessary licenses     arcpy.CheckOutExtension("3D")          # Coordinate System     prjfile = r'C:\Data\project.prj'     Coordinate_System = arcpy.SpatialReference(prjfile)               #Set parameters     Points1 = arcpy.GetParameterAsText(0)     Points2 = arcpy.GetParameterAsText(1)     Polygon = arcpy.GetParameterAsText(2)          # Parameters using elevation points for Create TIN tool     TIN1 = "test1"     TIN2= "test2"      Params1 = Points1 + " elev Mass_Points <None>"     Params2 = Points2 + " elev Mass_Points <None>"           # Create TIN models     arcpy.CreateTin_3d(TIN1, Coordinate_System, Params1, "DELAUNAY")       arcpy.CreateTin_3d(TIN2, Coordinate_System, Params2, "DELAUNAY")      instead of using a workspace I want to do everything in the current map but I am not sure how to use the arcpy.mapping module to read the layers into the map. I was thinking this might be an issue. Still new to this but I need to learn.


title: Planar CRS for raster and vector layers

text: I want to work with a planar coordinate system, and as far as I know QGIS automatically puts me in a cartesian plan if I don't set up a CRS (Coordinate Reference System) for my project. That is exactly what I want. The issue (may) begin when I import the raster image that I want to work with: it asks me to set a CRS for the image. The same happens when I create a vector layer for drawing features over my raster image: it asks me for a CRS for the vector too. The project remains without a CRS, but untill now I can not put any raster or vector without an CRS. For tests purposes I set up EPSG:32722 - WGS 84 / UTM zone 22S as the CRS for both raster and vector. I used UTM because I know it is based on a cartesian plan (though I'm not sure it's the best to do). My goal is to draw some polygons and calculate the area of that polygons. The scale is obtained from my raster (there's an object with known size in the image). I can't measure correctly the size of my object without setting the CRS of the project to be the same of the raster and vector, so I set the CRS of the project from the layer. It looks like the area is being correctly measured, but I can't know for sure if some transformation is going on. That said, my questions are: **Is there a way to import raster or create vector layers without a CRS (am I missing something)? Are my areas being calculated correctly this way? Is alright to use UTM for this purpose or there is a better option (maybe define a custom CRS)? ** (sorry for my bad English) QGIS 2.2.0 64 bits on Win 7 64 bits


title: OpenLayersPlugin doesn't work properly

text: I have some issues with the OpenLayers Plugin. I have already installed the plugin, though when i choose to add for example the google hybrid layer or anything else it doesn't do anything, just that it tries to load something.What should i do? thanks.![screenshot](http://i.stack.imgur.com/9zyvT.png)


title: How to find the watershed area for each point in the river network using DEM？

text: **Update#1** ： Thanks, Micha, I have followed your instruction and successfully use the modules in GRASS. I use **r.watershed** to get the basin raster and the drainage line： ![enter image description here](http://i.stack.imgur.com/MW08w.png) and I use **r.water.outlet** to get the watershed of one outlet： ![enter image description here](http://i.stack.imgur.com/xrPUK.png) I got **the whole basin area** of the green outlet point, but all I want is the little part of the original basin area, like this：part B is what I want ![enter image description here](http://i.stack.imgur.com/iNeUa.png) This schematic photo shows the idea of what I want： ![enter image description here](http://i.stack.imgur.com/pJhzs.png) Can I achieve this goal using **r.water.outlet** or other modules in GRASS？ Or all I can do is using the intersect tool in Geoprocessing tools in QGIS？ * * * As title, I want to find the watershed area, but using QGIS. I have following files to work with：   1. stream network shapefile(polyline)   2. point shapefile clipped from the polyline shapefile   3. a whole island(the stream is inside the island) DEM(I got 2 types:.lan & .tiff) I want to find the total watershed area located upstream of every point in the network, here's the schematic diagram： ![enter image description here](http://i.stack.imgur.com/tNL6u.png) the green, red, and yellow line enclose the watershed of each point(here I only take 3 points as the example), and I want to calculate their area. I already got the DEM file, and I must cut the region that contains the stream off, should I **polygonize** it first？Can I directly use this form(.lan or .tiff) to work with GRASS？


title: PostGIS, create line from points

text: I have a PostGIS table with position data of numerous vehicles and want to create lines from these points. Data can be selected by vehicle id and ordered by timestamp but how to create lines from the result? What I basically need is one line segment from point 1 to point 2, finalize the line and then again from point 2 to point 3. Of course all that under consideration of the vehicle id... The latter one is needed because I want to calculate the cruise direction and speed of the vehicle from one point to the next. Would be really nice to hear from you. Cheers Tom


title: Dynamic SLD styling based on min / max value in a PostGIS column

text: I have a PostGIS table that contains the GDP of countries together with their polygon boundaries. I am using GeoServer to display this data via OpenLayers. When styling the data, I want to avoid having to hardcode numeric range / colour pairs in my SLD file. Is it possible to create an SLD style file that dynamically determines the minimum and maximum value of GDP that are present in a PostGIS column, for example through CQL, and then uses that information to colour the map?


title: How to use CURRENT map document in Python tool?

text: I am attempting to use this code in a tool that I am working on:               mxd = arcpy.mapping.MapDocument("CURRENT")     df = arcpy.mapping.ListDataFrames(mxd)[0]     XMIN = df.extent.XMin     YMIN = df.extent.YMin     XMAX = df.extent.XMax     YMAX = df.extent.YMax      I then go on to do other calculations with the extent. The code works perfectly in the Python window, but because Toolbox tools are run in separate processes I am unable to use "CURRENT". I think I could probably add a derived input variable and pass the coordinates through the validation script, but that doesn't work for what I am doing. I need to be able to do this later on in the script and add an additional temporary feature to the current map:               points = arcpy.CreateFeatureclass_management("in_memory", "NewFeature", "POINT")     arcpy.AddField_management(points, "NewField", "TEXT", "", "", 20)      I know all of my code works right, because I can paste the entire .py into the Python window and then call `Main()` and run through it, but I need to share it with others in an easier way. I would prefer the solution be compatible with 10.0 and 10.1 if at all possible, because some of the people I work with do not have 10.1 yet. I will accept a 10.1 only solution if I have to though. What options do I have to do this? * * * UPDATE: I still can not get this to work, they have not gotten me Python Add- In Wizard yet so I am unable to test that approach. I have again tried the "Run in process" box checked and unchecked. Neither are working. Checked gives me this: `RuntimeError: CreateObject cannot open map document` Unchecked gives me this: ~~`ERROR 000714: Error in script ExtentQuery`~~ Handled that exception: `Object: CreateObject cannot open map document` From my testing looks like it is having the same error running in process or not. * * * UPDATE: ~~Apparently if you make a tool with no inputs it has really weird errors like this. As soon as I added an input variable I was able to make the script work as it was supposed to with "In Process" checked.~~ I will still be attempting to do this within the Add-In Wizard, when the finally give me it. Hopefully this afternoon. Thanks for the input and sorry for the confusion on this. The winning answer is I wasn't running it in the foreground.


title: Open source software to merge large shape files

text: Some background: I have 2 polygon shape files with approximately 500,000 records each. The two files are identical in terms of field structure. Using ArcGIS 10.0 I can'nt merge these two files using Geoprocessing / Merge. ArcMap allways crashes somewhere in the middle of the process. Is there any open source software that can do this job? QGIS has the function: Vector/ Merging shape file into one , but there was a reported bug with this function in the current version 1.7. I know GDAL can do a lot of things and wonder if GDAL or some other opensource software can do this properly.


title: Simple viewer for ArcGIS Projects?

text: I am a GIS analyst working for regional govt. I quite often have to create quite complicated interactive maps for non-gis users who need them for presentations. These non-GIS users then need to have ArcGIS experience in order to just disaplay layers. This often leads to confusion when for example the contents window has been switched off my mistake, and other little problems due to not having enough experience with the software. My question is...Does anyone know of any viewers which can basically display arcgis MXD documents but do not contain all the tools. I basically just need to display the layer groups/layers and keep their symbology, be able to switch the layers on and off, and possibly do a few other things like search for attributes, alter opacity. But the last two points are not really too important.


title: Looking for Cities population datasets for the state of Arizona

text: Looking for cities in Arizona especially I'd like to have them with that has population attributes. I've checked Arizona's geospatial websites and none of them I have found. Does anyone know where I can find them ?


title: ArcMap 10.2.1 issues diffferent SQL than 10.0 for "Select by location"?

text: I have a large point layer and I'm doing a "Select by Location" to select all points that intersect a specific selected polygon from a polygon table. In ArcMap 10.0 the SQL that was executed was basically the following:   1. Stick the se_rowid of the polygon into the sde_logfile_data table   2. Select all points that intersect the polygon In ArcMap 10.2 the SQL is an alternating sequence of:   1. Insert the rowids of 10000 points into the sde_logfile_data table   2. Select count(distinct sde_row_id) from sde_log_table where logfile_data_id = ... i.e., sde_logfile_data keeps getting inserted into and the subsequent selects take longer and longer. ArcMap ends up stalling and I have to kill it. Does this sound familiar to anyone?


title: Extracting values of one point shapefile to another point shapefile

text: I have a set of points along a river-channel which contain attributes to of the right and left riparian classification respectively. These points almost follow the channel center-line, and have been separated so that I have a point-shapefile with the right's bank classification and another shapefile for the left classification (let's call either shapefile as SHAPEF_CLASS). In the graphic below, the shapefile with the classification (desired attributes) is represented with the bold black dots. ![enter image description here](http://i.stack.imgur.com/uo00M.png) The colored dots represent another shapefile that contains bathymetric data (SHAPEF_BATHY). I would like to assign the river bank classification attribute from SHAPEF_CLASS to SHAPEF_BATHY. I tried converting the SHAPEF_CLASS to a raster (see below) with the intention to use the Identity tool to extract the classification values. However, the resulting raster does not cover the extent of the river channel so most of the bathymetry point are not covered. ![River classification points to raster](http://i.stack.imgur.com/hRS0J.png) I am using ARCMAP 9.3. I used the default cell size (0.000048), but if I increase the cell size I end up loosing some of the classes from the SHAPEF_CLASS. I thought about converting the SHAPEF_CLASS from point to polyline, and increasing the width of the line so it would cover the entire width of the river channel and then extract the classification. I also have a polygon of the river channel. Not if that would be useful for what I want to do though. Any suggestions would be welcomed.


title: QGIS Python Scripting - Syntax definition

text: After playing around with the Model Builder and looking at the python scripts of what I make, I noticed some syntax which I can't find the definition anywhere. Here is a snippet of the python script from a model:               outputs_13=processing.runalg("qgis:fieldcalculator", outputs_12['SAVENAME'], ID, 1, 10, 0, True, $rownum , None)     outputs_14=processing.runalg("qgis:deletecolumn", outputs_13['OUTPUT_LAYER'], longitude, None)     outputs_15=processing.runalg("qgis:deletecolumn", outputs_14['SAVENAME'], latitude, savename_alg15)     outputs_16=processing.runalg("qgis:clip", outputs_15['SAVENAME'], vectorlayer_layer1, None)     outputs_17=processing.runalg("qgis:fieldcalculator", outputs_16['OUTPUT'], Score, 0, 10, 0, True, 2, output_layer_alg17)      Can someone please explain the purpose of ['SAVENAME'], ['OUTPUT'] and ['OUTPUT_LAYER']? I am trying to develop a script but keep getting errors linked to these terms and I am unsure as to how they are used.


title: Network analysis point location error

text: I'm encountering a strange error using Network Analyst in ArcGIS 10.0. I have created a number of bus connections by repeatedly using Route analysis between a small set of point stops, producing a line feature class containing lots of partially overlapping lines. Creating a network dataset above them _and even calculating network locations_ with any points using the corresponding tool works flawlessly. The problem occurs when I finally need some analysis to be performed. Closest Facility and Route end with the following error:               Location does not have a corresponding network element. The network dataset     needs to be rebuilt.      for each of the stops involved. Service Area produces very strange results from which I'm unable to determine the problem. ![Service Area result](http://geocite.ic.cz/net.jpg) Is the problem located in the overlap of the lines? I even tried to build the ND with elevation fields corresponding to the original stops IDs so that each stop has an unique elevation, but that does not help in any way. Is there a way to work around the error or is it (perhaps) a bug? **EDIT:** Problem solved. The problem was in re-using the precalculated network locations in the stops layer that were valid for some other dataset but the default option of any Load Locations was to use them nevertheless. A foolish omission but hard to detect.


title: How to enable multithreaded processing in qgis 2.2

text: I have found multiple links that appear to say that this now exists in qgis 2.2, but it appears that it's only using one core to full capacity. This is running on Ubuntu 14.04 The current process is creating a large amount of regular points. How can I make that process use more than the one core? Thanks for the help!! ![CPU USage](http://i.stack.imgur.com/lLUS2.png)


title: NASA ASTER DTM - what is its datum? What are the elevations relative to?

text: I have downloaded some data from http://asterweb.jpl.nasa.gov/gdem.asp I would like to relate the elevations to some coastal data which is estimated to a specific ordnance dataum. Can anyone tell me what the datum (i.e. 0) refers to in ASTER data? Thank you very much


title: How to install Fiona to read Shapefile attributes with OSGeo4W?

text: I´m developing a plugin in Python and I need to read the shapefile attributes, so I found the Fiona API and dbfpy also but I don't understand how to install these packages because I install the QGIS through osgeo4W. How do I do that?


title: Moving openlayers from one geoserver to another geoserver

text: I created the layers on geoserver in development environment. Now i want to move few layers to another geoserver that is QA environment. I already moved the data required for the layers to QA environment. Now I want to move only few layers and stylesheet from Dev to QA. Is there any possibility? Srikanth


title: How to select a specific area (in a polygon form) determined by some value range in a raster band?

text: For example, I want create a vector layer with polygons that represents all areas where the elevation is between 500 and 600. Someone has any idea to help me? I'm using PyQgis 2.2.


title: WinBUGs giving 'Illegal memory write error' running under wine

text: Ok some I am trying to use Winbugs to do spatial smoothing. I am running r code in R study and using `R2WinBUGS` to call Wine 1.4 under Mac OSx Mountain Lion. It works ok for some models but for the CAR model I have set up Winbugs seems to run just fine until the very end when I am getting a Quartz X11 Blackbox error -I took a screen grab of the error box ![Quartz error box](http://i.stack.imgur.com/dI0zr.png) I cannot figure out what is causing this or how to fix it. Anyone come across this before ?


title: Convert / interpolate delimited text csv points grid to surface

text: I've got 12 delimited text csv files with regular pseudo-gridded points for temperature and salinity which look like this when zoomed in (inc distances) and this when zoomed out. I'm trying to convert them to a smooth surface layer - assumedly interpolated - but using the interpolation plugin on a vector layer saved from one of the csv's produced this kind of output, irrespective of how many columns I use. Please can someone suggest the best method to turn my grids of dots into a nice smooth surface that I can use colour interpolation on? Many thanks in advance. I feel that this should be really simple but I'm bashing my head against it and keep failing! Cheers.


title: How to extract coordinate pairs of crossing points of two polygons in PostGIS?

text: **Extracting coordinate pairs of crossing points of two polygons in PostGIS** Is it possible to extract x,y-coordinate pairs of crossing points of two overlapping polygons in PostGIS? Suppose there are only 2 overlapping points of the polygons the `ST_Intersection` function extracts more than two coordinate pairs (also the shared vertices of polygons are included).               SELECT ST_Intersection(geometry geomA , geometry geomB);      I am interested only in the 2 boundary crossing points of polygons.


title: QGIS: plotting real time lat/lon GPS input on a different projection

text: I'm trying to plot realtime GPS over a satellite image in QGIS 1.8. The GPS data is coming in as NMEA lat/lon from a Garmin Etrex. This works when the image is in WGS84 lat/lon projection and therefore the coordinate systems match. Unfortunately, I will be using this in high latitudes and WGS84 becomes unusable. I'd much rather have the image in something like UTM 24N or polar stereographic. Does anyone know a way to get the GPS to plot in the right location? I don't seem to be able to change the coordinate system that the GPS outputs, only the on-GPS display. Suggestions for either Linux or Windows welcome!


title: Is it possible to use DotNet to show a QGIS map?

text: Has anybody ever tried to show and interact with a QGIS map from a DotNet language like C#? What i have in mind is, to write a desktop application with C#, and show an embedded map with the QGIS-API on a form. The most useful document i found, is this Coding Guide, and it seems that QGIS supports exclusively C++ and Phyton to write applications/plugins. So my question, is it doable to create DotNet wrappers in C++, and use them in a managed language (with a reasonable amount of work)? Any positive or negative experience?


title: How to avoid cutting labels along the map border?

text: I am labeling areas on a map (for example, forest (coniferous, deciduous trees), swampland, and so on). A cartographer has criticized it because labels which extend beyond the boundaries of the specific areas are cut off. Therefore, **I would like to show only those labels that are _completely_ contained within the area.** (I tried to work around the problem by masking the area with an internal buffer of the area's border, but that only cuts the labels along the buffer boundary.) I would appreciate any ideas about how this could be accomplished with QGIS 1.80.   * Thank you, whuber, for your assistance*


title: FME - what is the difference between "generate workspace" and "create workspace"?

text: as a newbie to FME i can´t really understand the basic difference between the two ways of making a workspace. Generate or Create. Can someone explain the difference? Thanks, Rob


title: how to improve poi visualization in tilemill

text: I have imported all points of interest (POI) from database to TileMill. The distance between the POIs are a few meters. Thats is why its became ugly looking map. Is there any option that will aggregate POIs those are within 100 or 500 meter?


title: Some tiff not included on a vrt index

text: I have some tiff files and I'm trying to generate a vrt index with gdal tool, gdalbuildvrt. I run this command:               gdalbuildvrt orto_index.vrt -srcnodata "0 0 0" -vrtnodata "0 0 0" *.tif      and throws the next warning:               Warning 6: gdalbuildvrt does not support rotated geo transforms.     Skipping 2335-C.tif      So there are some tiff that are skipped. If we compare the information about a skipped file with another that it has not skipped, we could see the next difference: In the skipped file, we can see the next line:               GeoTransform =       345770.7884398972, 0.6000000238418568, 3.473043927400512e-15       6139634.558238117, 1.757016748640284e-14, -0.6000000238417672      In the non skipped file, the other one:               Origin = (223499.236031105130678,6213152.835421450436115)     Pixel Size = (0.600000023841858,-0.600000023841858)      How can I make to get a vrt file including all files, I mean, without skip some files?


title: ArcGIS JavaScript API filter raster dataset

text: I have around 1000 rasters (b&w tiffs) and most of them overlay each other. At this moment, I'm holding them in mosaic dataset and I want them to be displayed in my javascript webapp. I am able to load it as Dynamic or Image service layer and it loads all the rasters at once. In screenshot below, mosaic's attribute table has field "Name" in which names of all the rasters are held (all names are unique to only one raster). In my webapp, I want to dynamically show only one raster by specifying its name. Part of mosaic: http://i.imgur.com/RB2zl52.jpg In arcmap I can use layer's definition query to select only particular raster (screenshot below). Filtered by definition query: http://i.imgur.com/XDkFl8y.jpg What would be the appropriate approach to have dataset filtered in webapp?


title: Color Ramp of Raster Rendering in MapServer

text: Does this proposed new syntax work yet? http://mapserver.org/development/rfc/ms-rfc-6.html#proposed-new-syntax Currently, I am still using this method for rendering the raster in Mapfile.               STYLE        COLORRANGE 0 0 0  255 255 0 # black to yellow        DATARANGE 0.0 100.0        RANGEITEM "foobar"     END      However it doesn't work so well since it is linear interpolation and equal interval. In reality, the histogram of raster shows that data doesn't distribute with equal interval. In ArcGIS, the default method for classified raster rendering is Natural Breaks (Jenks). Is there any new improvement for that in MapServer? Thanks


title: ArcGIS API Javascript - FeatureLayer from json: problem with queries and popup

text: Hello everybody   I've tried this code proposed by Derek Swingley in JSFIDDLE:   JSFIDDLE-FeatureLayer from JSON   Everything "seems" to work fine, but not always. If you go down to the closer scale (level 21 I suppose) and click several times on different points of the line, sometimes you get a popup with the text "(1 of 3)" in the black section of the popup and sometimes you get the text "Buck Creek 3". Once you press in the arrow keys of the popup, this title doesn't return, you will always have the "(x of 3)" text and, besides, the order is a bit strange. Pressing the right arrow, it passes from "Buck Creek 3" to "Buck Creek 2" and after that to "Buck Creek 3" again. It's needed to press several times the left arrow to get to "Buck Creek 1".   I have built a similar example, replacing lines with points in the json. In this case, I never get the "(1 of 3)" text when the popup has just opened. Now, similarly, if I press the arrow keys of the popup, I always get the "(x of 3)" text. And with points I have same problem with the order.   I think the problem is related to the matter that the feature layer is coming from a JSON, because if I create it from an ArcGIS Server URL I'm not able to reproduce the problem. But the problem is that I need to take the data from the JSON.   Do you know if it's possible to modify this behavior? I prefer having the "(1 of 3)" text from the very beginning and see the elements in the right order.   Thanks in advance,   Santiago


title: ST_Distance versus ST_Distance_Spheroid?

text: As my client software uses lat/lon coordinates when communicating with my (spherical mercator) postgis database i decided to ST_Transform every geometry to WGS-84. However i noticed that ST_Distance for WGS-84 returns units as degrees (i need meters). So i decided to use ST_Distance_Spherical(geom1, geom2, 'SPHEROID["WGS 84",6378137,298.257223563]') but this method seems to be extremely slow. Therefor i switched back to using spherical mercator again and transforming my input and output to and from wgs-84 as that performs a lot better. Am i using the correct method or is this a known issue?


title: Where can I find Population data for all UK Counties?

text: Where can I find population data (male, female, total) for all UK counties for last 7 decades, i.e. 1950,1960,1970,1980,1990,2000,2010. I tried my luck with Office for National Statistics and UK National Statistics, but all in vain.


title: Is there any API in C# for Zooming selected feature?

text: I am new to ArcGIS and want to implement the **Zoom to Selected Features** functionality available in Selection menu option (Selection-> Zoom to Selected Features), using C# API. Is any API available in C# ?


title: The next big thing in standardized spatial data exchange format?

text: I remember reading something a few months back, in the latter half of 2012, about a coordinated group effort to design a new standard for sharing geographic / spatial data. It has or aims to have the potential of replacing the showing-its-age (20+ yrs) de-facto standard of the Esri shapefile as the means of choice for widely sharing our data across all devices and platforms. Aside from addressing the most pressing shapefile limitations, this new thing incorporates raster and metadata too. This big-important-thing I don't recall is not SpatiaLite - Shapefile of the future? or Are there any attempts to replace the shapefile? but some of the conversation swirling around it was similar. I spent quite some time today trying to track this down, but my search-fu proved not up to the task (which might not bode well for its future). Please, what is the name of this elusive project that has the potential to deeply impact all our workflows? (Assuming it gets off the drawing board, lord knows we need _something_ to.) And, how or where does one get involved or at least keep track of it?


title: ArcPy- AddJoin-function struggles using Table of PersonalGeodatabase

text: ## Hey, I am doing some arcpy -functions and afterwards I'm trying to add the calculated results from one table to another table. I'm using the `arcpy.AddJoin_management()` function. As input table I'm using a table which is stored in a personal geodatabase. The personal geodatabase is not the workspace environment! As "JoinTable" a Table of a file geodatabase is used. This file geodatabase is the workspace geodatabase environment. The initialized function looks like this: (%self.getWorkspaceEnvironment => "W:/a18fb/data/mypersonalgeodatabase.mdb" and tFactsheetHochwasser => table in the personal geodatabase) `arcpy.AddJoin_management("%s/tFactsheetHochwasser"%self.getWorkspaceEnvironment(),"KPG", "GebaeudeKtn_BWVred1Stat","KPG","KEEP_ALL")` If the code is executed the following error-message appears: Failed to execute.Parameters are not valid. The value cannot be a table > ERROR 000840: The value is not a Raster Layer. > > ERROR 000840: The value is not a Raster Catalog Layer. > > ERROR 000840: The value is not a Mosaic Layer. > > Failed to execute (AddJoin)`. So, I would be thankful for any ideas!!


title: How to find out whether a lat/long position resides within a Polygon?

text: I'm working on a system that stores latitude/longitude information of addresses in a PostGIS table. To store Lat/Long in geometry data type I'm using ST_GeometryFromText function. For example the following function call gets the geometric value against the specified Long/Lat position:                myPointGeo =  ST_GeometryFromText('POINT(40.758871 -73.985114)');      Similarly, I convert a Polygon into geometric representation as follows:               myPolygonGeo =  ST_GeometryFromText('POLYGON ((40.7566484549725 -73.9878561496734, 40.7556894646734 -73.9853026866913, 40.7545841705587 -73.9860537052154, 40.7548036054111 -73.9881458282471, 40.7559820394514 -73.9887895584106, 40.7566484549725 -73.9878561496734 ))')      I want to find out whether the above lat/long position resides within this Polygon or not. For this I'm using ST_Within function. But though 'myPointGeo' actually resides within the Polygon, ST_Within is returning false. I'm using ST_Within this way:                St_Within(myPointGeo,myPolygonGeo)      What am I doing wrong here? Should I use some other function for this purpose?


title: Looking for tool to start ArcGIS for server 10.1 services automatically

text: Is there any tools or scripts to start ArcGIS server 10.1 services automatically when the services are stop? Thanks


title: How to split zAware polyline by points programmatically with C#?

text: I'm trying to split a polyline by the boundaries of a polygon using IPolyCurve2.SplitAtPoints using C#. The polyline I'm trying to split is zAware and holds elevation values at a regular interval. After splitting the polyline I would obviously like to get the different parts and save them as new features in my feature class, then deleting the original one. The problem is that when I try to set feature.shape to the geometry in my geometry collection made up of all the polyline parts, I get the error message that the geometry has no Z values. Does anybody know how to solve this issue? I've looked around in the forum but all I found was code that doesn't deal with polylines that hold Z values. Thank you very much! Here is the code I'm using, passing in the original polyline, the point collection that holds all the intersection points with the polygon and the original feature class I create new features in.               public void SplitPolylineFeature(IFeature pPolylineFeature, IPointCollection pSplitPointCollection, IFeatureClass pFeatureClass)         {             //split the feature, each split makes a new part             IEnumVertex pEnumVertex = pSplitPointCollection.EnumVertices;             IPolycurve2 pPolyCurve = pPolylineFeature.Shape as IPolycurve2;             IEnumSplitPoint pEnumSplitPoint = pPolyCurve.SplitAtPoints(pEnumVertex, true, true, -1);             object Missing = Type.Missing;                  if(pEnumSplitPoint.SplitHappened)             {                 //new geocoll for polycurve                 IGeometryCollection pGeometryCollection = pPolyCurve as IGeometryCollection;                      //loop through the parts of the split polyline                 for(int intPartCount = 0; intPartCount < pGeometryCollection.GeometryCount; intPartCount++)                 {                     IGeometryCollection pLineGeoColl = new PolylineClass();                     IGeometry pGeometry = pGeometryCollection.get_Geometry(intPartCount);                     //IZAware zAware1 = (IZAware)pGeometry;                     //zAware1.ZAware = true;                          pLineGeoColl.AddGeometry(pGeometry, ref Missing, ref Missing);                          IFeature pFeature = pFeatureClass.CreateFeature();                          pFeature.Shape = pLineGeoColl as IGeometry;  //code crashes here: Geometry has no Z values                     pFeature.Store();                      }             }             pPolylineFeature.Delete();         }


title: Creating spatially projected polygon grid with ArcMap

text: i need to create a grid with 1x1 square kilometres cells in ArcMap. The operation located in Data Management Tools -> Feature Class -> Create Net is almost what i need but in the parameters, i can't define a projection the raster grid ist based on. The raster grid must be in the Projection UTM 32N, not in an "undefined" projection. Is there any operation/function in ArcMap i can use to create a spatially projected polygon grid? Thanks in advance


title: Passing extent from web map to PDF for integration?

text: I'm trying to figure out whether I can take an extent (or coordinatess with a Zoom level included) to a PDF in order to author a PDF that displays both GIS and report-styled business data? Is this something possible with ArcGIS API for JavaScript or even via Flex?


title: no viewable feature when creating line with ogr in python

text: the python code below produces the expected line shapefile viewable in QGIS               import os     from osgeo import ogr          drv=ogr.GetDriverByName('ESRI Shapefile')     if os.path.exists('test.shp'):         os.remove('test.shp')     ds=drv.CreateDataSource('test.shp')     lyr=ds.CreateLayer('test',None,ogr.wkbUnknown)     flddef=ogr.FieldDefn('Name',ogr.OFTString)     flddef.SetWidth(32)     lyr.CreateField(flddef)          feat=ogr.Feature(lyr.GetLayerDefn())     feat.SetField('Name','george')     line=ogr.Geometry(ogr.wkbLineString)     line.AddPoint(1116651.439379124, 637392.6969887456)     line.AddPoint(1188804.0108498496, 652655.7409537067)     line.AddPoint(1226730.3625203592, 634155.0816022386)     line.AddPoint(1281307.30760719, 636467.6640211721)     feat.SetGeometry(line)     lyr.CreateFeature(feat)          feat.Destroy()     ds.Destroy()      however, when attempting to use the sqlite driver, the database and layer is created with no errors. QGIS can connect to the database and load the layer - though nothing is displayed.               drv=ogr.GetDriverByName('SQLite')     if os.path.exists('test.sqlite'):         os.remove('test.sqlite')     ds=drv.CreateDataSource('test.sqlite',options=['SPATIALITE=yes'])     lyr=ds.CreateLayer('test',None,options=['FORMAT=SPATIALITE'])     flddef=ogr.FieldDefn('Name',ogr.OFTString)     flddef.SetWidth(32)     lyr.CreateField(flddef)          feat=ogr.Feature(lyr.GetLayerDefn())     feat.SetField('Name','george')     line=ogr.Geometry(ogr.wkbLineString)     line.AddPoint(1116651.439379124, 637392.6969887456)     line.AddPoint(1188804.0108498496, 652655.7409537067)     line.AddPoint(1226730.3625203592, 634155.0816022386)     line.AddPoint(1281307.30760719, 636467.6640211721)     feat.SetGeometry(line)     lyr.CreateFeature(feat)          feat.Destroy()     ds.Destroy()      on win7, python 2.7.5 (python (x,y) distribution) BTW - creating a point feature rather than a line works for both cases. also tried removing the spatialite option from the datasource and layer creation - no change. am i missing some obvious step?


title: Return column number of min value in dataframe

text: So as a result of a bunch of preceding calculations I end up with a dataframe of varying numbers of rows and columns. I want to find the minimum value of the df and return the row and column index. How can I do this ? For example the below data is a typical output:               row.names   2838        2849        2865     2768        9118.4184   14548.0008  6118.441     2769        10749.0109  18873.3781  14490.520     2775        11336.9757  19230.1397  13515.399     2780        3535.5576   11619.9425  5497.814     2842        2946.4059   10614.0673  5994.932     2843        127.0874    5250.5626   6012.107     2844        11684.4736  3851.1980   13670.723     2846        449.1957    149.3105    6171.846     2862        8574.5068   8143.8069   14397.451      This line will correctly give me the row index of the lowest value (127.0874):                   > which(df==min(df))         [1] 6      But what command will return me the column index for the minimum value?


title: Multiply point values by raster values

text: I have a point shapefile containing elevation values in the id field. The shapefile is overlaying a raster layer of the topographical slope. Is it possible to multiply the elevation value of each point by the respective slope value of the raster cell laying immediately below the point?


title: Identify circuits/loops in GPS track data

text: This question will be naive and uneducated, but I gotta start my research somewhere, so I'll ask for references and pointers... Let's say you have a GPS time series with a set of lat/long coordinates per second, how would you go about identifying circuits/loops in that GPS track? To the layman, it seems like something that should be possible, but I suspect it could just as well be a tremendously complicated problem.


title: ArcGIS SDK for .Net (used in WPF): update map's zoom parameters after changing base layer

text: I'm having the following issue:   Suppose I have a Map object and 2 base layers (a world map and a street map). A world map doesn't let us view the map too closely. The street map allows us to view as close as we want (almost). So, they have different scale parameters. Now, if I load the world layer first, like this (pseudocode):               map.Layers.Insert(0, WorldLayer);      and then switch layers:               map.Layers.Remove("WorldLayer");     map.Layers.Insert(0, Streetlayer);      The map doesn't allow me to get closer than a WorldLayer allowed. SO, actually, I can't view a street view normally. BUT, if I load a detailed map first:               map.Layers.Insert(0, Streetlayer);      and then switch layers:               map.Layers.Remove("Streetlayer");     map.Layers.Insert(0, WorldLayer);      In this case I can freely view trees near my home :) And even if I switch back, the WorldLayer would allow me to get closer than it allowed before. I suppose there should be a way to update a map, to renew scale/zoom parameters for a new set of layers. Is anyone aware of a way to achieve that?


title: QGIS Road graph setting not configure

text: I am using qgis valmiera on windows 7 pro 64 bit. I am unable to configure road graph setting. Layer feature Transport layer is not highlighted. Please tell me how to solve this problem. Please tell me also how to manually configure CRS. that is user defined coordinate system, so that i can manually enter the values of projection.


title: Trigger event on right-click

text: I want to, on right-click on a feature in a layer, have an action execute. I need to know 1 thing: What layer was right-clicked. Does anybody know how I can get this functionality? The API doesn't officially support it.


title: How to get the Measure Line in Yards (not Feet)

text: I'm using Qgis Dufour 2.0.1 and the Openlayers Plugin for images. I'm working on a golf course project where everyone thinks in yards. I've tried different CRS (now working the State Plane Missouri East in FEET). The measure tool units match this CRS EPSG 102696. Is there a simple way to change the CRS code so that measurements will be in Yards rather than in US-feet?


title: Using ArcSDE on an Oracle DB, how can I tell which users have permissions to a Feature Class

text: I created a new `Feature Class`, and I assigned some users `SELECT` privileges to that `Feature Class`. I want to look at the list of users that I have assigned privileges to, how do I do that? **Updated** Is there a GUI application to do this?


title: Install Mapserver on Mac OS 10.9 with macports 2.3.1

text: Does anyone have experience installing mapserver on Mac OS 10.9 with macports? It seems that there is one version, mapserver 6.2.1_2 supported by macports. However, whenever I tried to install it, I always got result as in the image below. ![enter image description here](http://i.stack.imgur.com/2ETVR.jpg) Does anyone have any idea about how to fix this problem? Many thanks in advance :) //Yvan


title: How to connect to CouchBase with ogr2ogr?

text: I am trying to load a Shapefile to CouchBase (version: 2.5.0 DEV edition, installed on Ubuntu), but with no success. According to this documentation it is possible like this: > ogr2ogr -f couchdb "couchdb:http://some_account.some_couchdb_server.com" > shapefile.shp so I tried like this: > ogr2ogr -f couchdb `"couchdb:http://localhost:8092"` shapefile.shp or > ogr2ogr -f couchdb `"couchdb:http://localhost:8092/osm"` shapefile.shp (where osm is an existing databucket) and also with permissions: > ogr2ogr -lco UPDATE_PERMISSIONS=ALL -f couchdb > `couchdb:http://localhost:8092` shapefile.shp then I tried simply to connect: > ogrinfo -ro `"couchdb:http://localhost:8092"` which gives me the error: > FAILURE: Unable to open datasource `'couchdb:http://localhost:8092'` with > the following drivers. [list of drivers including couchdb] I also tried 127.0.0.1 instead of localhost and also with port 8091 (and every combination of these). Can anyone verify that the couchdb ogr2ogr driver is working? And if yes, what am I doing wrong? Maybe the problem is that it is CouchBase instead of CouchDB?   My GDAL version is 2.0.0dev   I am grateful for any suggestions.


title: ExportToJPEG() arcpy script failure

text: I'm attempting to writing a python script that will automate exporting a set of stock maps to JPEG from their mxd files, and I'm having some strange issues getting there. I've alternatively been getting a Visual C++ Runtime error saying python experienced an abnormal program termination, or the program throws an exception saying "AttributeError: PageLayoutObject: Error in executing ExportToJPEG" I've tried two main ways of running this process. In one I loop through an array of directories and pull the individual mxd files into the export command, as below:               for line in Direct:         path = str(line) + "*.mxd"              listing = os.listdir(path)         for infile in glob.glob(path):             mxd = arcpy.mapping.MapDocument(infile)             infile = infile.split("\\")[-1]             infile = infile.rstrip('.mxd')             infile = infile + ".jpg"                  project = os.path.join(destpath, infile)             arcpy.mapping.ExportToJPEG(mxd, project, resolution = 200)                  del mxd      In the other form, I copy the arcpy.mapping.ExportToJPEG() line over and over with the parameters for each map specified, as below:               mxd = arcpy.mapping.MapDocument(r"Y:\Maps\map1.mxd")     project = "C:/Maps/map1.jpg"     arcpy.mapping.ExportToJPEG(mxd, project, resolution = 200)          mxd = arcpy.mapping.MapDocument(r"Y:\Maps\map2.mxd")     project = "C:/Maps/map2.jpg"     arcpy.mapping.ExportToJPEG(mxd, project, resolution = 200)          mxd = arcpy.mapping.MapDocument(r"Y:\Maps\map3.mxd")     project = "C:/Maps/map3.jpg"     arcpy.mapping.ExportToJPEG(mxd, project, resolution = 200)      I've tried multiple tests to see if my syntax is wrong, and if the script is using too many resources and crashing, but haven't been able to figure out what my issue is. The weird part is I can't seem to find any pattern or reason to the maps I'm getting these errors on. It seems like it changes every time I alter my script.


title: Calculate and Label the lengths of polygon edges/sides

text: I have got a map-server, postgresql/postGIS & Google map API implementation. Users will draw polygon features after logging in. I would like to Label the sides/edges of a polygon with length values. How can I calculate these individual lengths and Label using the same?


title: How to prepare automatic text labelling for legend using arcmap?

text: I need to label for text with legend without ungrouping layers. I have attached an example image to show the expected output model I am looking for your guidance. Thanks in advance. ![enter image description here](http://i.stack.imgur.com/wKMAk.jpg)


title: How to update ArcGIS 10.0 extension for ArcGIS 10.1?

text: I have an ArcGIS 10.0 extension which will no longer install for users who have upgraded to ArcGIS 10.1. Are there a defined set of changes that need to be made in order to upgrade the extension, or is it dependent on extension options, such as the libraries that are called? The error recieved upon install is: `"Error 1001. Unable to get installer types in the C:\...extensionname.dll assembly. --> Unable to load one or more of the requested types. Retrieve the LoadedExceptions property for more information."` Any other comments/advice on moving extensions to 10.1?


title: Debugging ogr2ogr "AddGeometryColumn failed" and "Terminating translation prematurely after failed translation of layer"

text: As noted in the title, I'm getting the following error:               ERROR 1: AddGeometryColumn failed for layer pretty_polys, layer creation has     failed.     ERROR 1: Terminating translation prematurely after failed     translation of layer mybeautifulshapefile (use -skipfailures to     skip errors)      I'm just adding a shapefile to PostGIS using ogr2ogr (PG connection data is all fake placeholders, obviously):               ogr2ogr \         -f PostgreSQL \             PG:"host='000.00.000.00' port='5432' user='nullislandpatriot' password='nullisland4eva' dbname='data_i_like'" \         "data/mybeautifulshapefile.shp" \         -nln pretty_polys \         -nlt POLYGON      I've tried to identify many possible sources for the error, but I can't seem to figure out what's wrong, and the error isn't descriptive enough. So my question is, **how can I drill down into this error to find out why AddGeometryColumn is failing?** Here are some of the things I have already tried:   * using different files. I receive this error with any file, including the natural earth countries shapefile   * checking the permissions in PostgreSQL. I have read and write access to the public schema that is being used. Though I should note that I am not the superuser, and we had to give explicit permission to allow me to access `spatial_ref_sys`, and `geometry_columns`.   * editing the `-nlt` option to make sure I'm using the correct geometry type.   * checking different arrangements of `-a_srs`, `-s_srs`, `-t_srs`, and not using them at all.   * lots of other things before I tried the natural earth data, like PRECISION=NO, different database schemas, text encoding, ... My assumption is that the error has something to do with permissions or settings in PostgreSQL or the syntax for the connection info, since I get the same error for well-known shapefiles like Natural Earth. I've tried the connection info withou the interior single quotes. I also tried `CPL_DEBUG=ON`, which shows me a bit more of what is working:               Shape: DBF Codepage = UTF-8 for     /Users/bgolder/Downloads/ne_10m_admin_0_countries/ne_10m_admin_0_countries.shp     Shape: Treating as encoding 'UTF-8'.     OGR:     OGROpen(/Users/bgolder/Downloads/ne_10m_admin_0_countries/ne_10m_admin_0_countries.shp/0x7f9a79d00720)     succeeded as ESRI Shapefile.     PG: DBName="'data_i_like'"     PG: PostgreSQL version string : 'PostgreSQL 9.1.9 on x86_64-unknown-linux-gnu,     compiled by gcc (Ubuntu/Linaro 4.6.3-1ubuntu5) 4.6.3, 64-bit'     PG: PostGIS version string : '2.0 USE_GEOS=1 USE_PROJ=1 USE_STATS=1'     OGR_PG_NOTICE: NOTICE:  CREATE TABLE will create implicit sequence     "countries_ogc_fid_seq" for serial column "countries.ogc_fid"          OGR_PG_NOTICE: NOTICE:  CREATE TABLE / PRIMARY KEY will create implicit index     "countries_pkey" for table "countries"          ERROR 1: AddGeometryColumn failed for layer countries, layer creation has     failed.     ERROR 1: Terminating translation prematurely after failed     translation of layer ne_10m_admin_0_countries (use -skipfailures to skip     errors)          GDAL: In GDALDestroy - unloading GDAL shared library.      Specs:   * PostGIS 2.0, with PostgreSQL 9.1.9 on Ubuntu 12.04   * GDAL 1.11.0 (on OS X 10.9.3, installed via Homebrew)


title: Ground Sampling Distance

text: I am quite new to QGIS. I got an Orthophoto under QGIS. I want to calculate Ground Sampling Distance values of this image. Does anyone know how to do this under QGIS? I am using QGIS 2.2.0. I even don't know where to find the values under QGIS for the GSD-formular..


title: Need help understanding why gdal projections aren't giving me what I expect?

text: When using gdaltranslate and gdalwarp I specify the following transfomation (in for GCP's and translate, out for warp)               +proj=lcc +lat_1=40.03333333333333 +lat_2=38.73333333333333 +lat_0=38 +lon_0=-82.5 +x_0=1968500 +y_0=0 +ellps=GRS80 +datum=NAD83 +units=us-ft +no_defs      This is intended to be the proj4 equivalent of Ohio South state plane US feet. If I open it in GlobalMapper it is placed exactly correctly (about -83 lon) though it isn't identified as Ohio South. However when I run listgeo the coordinates in feet are listed, but the lat long are not shown, and if I run gdalinfo the coordinates come back as               Upper Left  ( 1747866.344,  712518.960) ( 99d 6'46.00"W, 38d45'47.64"N)      with the longitude being completely off base. I also notice that the false_easting in gdalinfo come up as               "false_easting",6458320.416666666      which I also don't understand since I set it directly in the projection as 1968500' In the end what I really want to do is digitize some coordinates in state plane, US survey foot, run them through translate to create a VRT file, then warp that and output Geotiff that has a recognized projection and will read directly into Global Mapper. I tried just using a prj or wkt file, but once I edit it to change the units to feet then the resulting Geotiff has the following tags either deleted or set wrong. GTModelTypeGeoKey (Short,1): ModelTypeProjected (ends up user-defined)   ProjectedCSTypeGeoKey (Short,1): PCS_NAD83_Ohio_South (ends up missing) Any thoughts on what I am doing wrong would be greatly appreciated.


title: How to change the language of all Web Applications of the ArcGIS Server manager (for ASP.NET)?

text: ArcGIS Server manager (ASP.NET) comes by default the English language. I would like to configure it to Portuguese of Brazil. It is ok if the administrative tool is in English. But I'd really like is that the maps Labels were in Portuguese. As in the words: Results, "Query Attributes", "Find", and others. So my users to access my Web Applications in the native language of maps here. I know I could edit the Labels in Visual Studio (VS), but this is laborious. And my co-workers do not know how to work in VS. Because I'm the Analyst Informatics and they cartographers. VS is complex for them who do not know how to program. How to configure all Web Application to another language? Thank you!


title: Joining lines in MapInfo that won't be split by disaggregate?

text: I have just run a disaggregation a .tab containing just lines and found I have a few with duplicate IDs. However when I zoom in these lines appear to be connected. Is there any way to join these together so they won't be split up next time it is disaggregated? Thanks, Alan


title: Calculate number of people within 50 km of a point

text: I have two data sets:   * World population (raster) in EPSG:4326, from http://sedac.ciesin.columbia.edu/data/set/gpw-v3-population-density-future-estimates/data-download   * A shp file with points (distributed around the globe), also in EPSG:4326 I would like to calculate the number of people within for example 50 km from each point. What would be the best way of doing this in QGIS? Best regards, Magnus


title: arcmap replica error number and description list

text: We have a replica between our sql server geoDB and another sql server geoDB. It is a one-way replica and our geoDB is the child. Recently an error occurs (error 000582). I searched for the cause of the error and got from ESRI forum which said "This error can occur if one or more of the feature classes and datasets are not versioned or don't have GlobalIDs." Details check https://geonet.esri.com/thread/52003. "the feature classes and datasets are not versioned or don't have GlobalIDs", may I confirm is the issue from the parent side? Now the user want to see the official support for description of the error, but I failed to find it. I want to check whether there is a source which list all the replica errors and the cause for them. I am using arcsde 10.1, thanks.


title: Where can I set GetLegendGraphic width?

text: Given a wms-service, the GetCapabilities request returns a legendurl like the following:               <LegendURL width="186" height="22">      If I specify a width (like below) when using GetLegendGraphic, it is ignored, and the width in LegendUrl is used.               http://myserver/wms/?LAYER=mylayer&SERVICE=WMS&VERSION=1.1.1&REQUEST=getlegendgraphic&FORMAT=image/png&WIDTH=300      Where can I change the LegendUrl width? or alternately, how do I use the width setting?


title: OziExplorer maps not rendered correctly in QGIS

text: When I open up some OziExplorer (.ozf2) maps in QGIS they are not rendered correctly in that they appear reversed or in-versed. Text on the map is not legible and looks to be in-versed but this is not the case (looking via a mirror confirms this). Find this very strange and looking for some help. Maps from http://maps.festy.org/


title: How do I classify number values in Python to assign it to a group?

text: I have calculated the number of points that exists for a SqMi area and am trying now to assign it to a certain group based on where it falls in the classification. Does anyone know a tool that I can run that will generate an output, or the python code that will help me to test these values to see where they need to be. I have inserted a sample code and I will write some pseudo code so that you can follow my logic to help.               #Calculate per sq mi the number of incidents within the zone (Top=15+, High = 12-15, Some = #6-12, Low = >6)     # Get the shape_area number from the CurrentZoneLayer     field = "SHAPE_Area"     with arcpy.da.SearchCursor("CurrentZoneLayer",field)as cursor:         for row in cursor:             zoneSqMi = (row[0]/2589988.11)             print "Zone SqMi: "+ str(zoneSqMi)          # Divide the zoneSqMi by the number selected to get points by SqMi     pointsPerSqMi = numSelected/zoneSqMi     print "Points Per Sq Mi: " + str(pointsPerSqMi)          # Create a series of tests to see which group the points will fall under Top, High,  #Some, Low     # if pointsPerSqMi > 15 then print "Top"     # if pointsPerSqMi <15 and pointsPerSqMi      Eventually these categories will be written into a field value as well, but for now I am just trying to figure out the logic on how to assign it to a group within a script.


title: QGIS import polygons in CSV

text: QGIS 1.8 on Mac: I'm hoping to migrate several dozen local maps from my 30 year old Win3.1 plotting system to QGIS. Polygons are in X,Y (CSV), first point repeated at the end to close it, with polygons separated by a blank line. They're each in local coordinates (meters from a corner). I can transform to UTM and replace the polygon delimiter by something else if needed, but it would be easier not to have to. The format is               10,10     20,20     20,30     10,10          5,5     5,6     6,5     5,5      I've tried Import as Text Layer: the attribute table shows the values correctly, but each coordinate only shows as a point, the polygon separator lines are omitted, and the layer can't be edited. Tried to export it as vector layer as http://maps.cga.harvard.edu/qgis/wkshop/import_csv.php suggests- export fails. I can't find the mmqgis mentioned in several posts here; the Points2One plugin doesn't do anything. Any suggestions?


title: How to upgrade QGIS Capiapo to Lisboa?

text: I want to upgrade my QGIS version to the newest one, Lisboa, but I'm not sure if I should uninstall Capiapo first. Is there a way to upgrade without uninstalling? Thank you.


title: Aggregate Data between Polygons

text: I have data at the ZIP3 level and I need to join it to a state file. I also need the data within the zip3 file to be averaged, but for some reason when I use the join tools, i'm not getting the results that I need. Is there a way to aggregate data from a zip3 level to a state level without swtiching over to raster data (which is what the spatial analyst tool requires). Thanks!


title: Ogr2Ogr exported this boundary 90 degrees incorrectly

text: I've got some `GEOGRAPHY` data in my Sql Server 2008. I wish to export it as a shapefile (so I can import it into QGIS) and when I do, it's rotated 90 degrees to the left and then flipped 180 degrees to the right. ## Command line               C:\>ogr2ogr -f "ESRI Shapefile" "C:\temp\test.shp" "MSSQL:server=dbserver; database=xwing; uid=xwing; pwd=dbpwd"                 -sql "SELECT OriginalBoundary FROM Geography Boundaries where LocationId = 18561"                 -overwrite                 -lco "SHPT=POLYGON"      ## Boundary is Sql Server 2008 ![enter image description here](http://i.stack.imgur.com/n53gXt.png) ## Boundary loaded into QGIS after using Ogr2Ogr ![enter image description here](http://i.stack.imgur.com/QaxuZt.png) /me sad panda.


title: Getting started with storing LoST and GML searching

text: I am working on a logging and search database application. The application will receive event records containing XML LoST values (RFC5222 Location-To-Service-Translation). These records will be stored in a PostgreSQL database. The application will later need to search for those event records using GML Polygon, Circle, ArcBand or Ellipse areas. Can someone give me a pointer of where to get started with this?


title: How to determine which stream end point is at the basin outlet?

text: I am working with streams, stream end points, elevation raster and I have created basins using the watershed tool in ArcGIS. From that data, I would like to determine for each basin, which single point is at or nearest the outlet as shown by the arrow in the example below. ![enter image description here](http://i.stack.imgur.com/GyDrR.png)


title: How to convert the OSM coordination system to map another?

text: I have used SVG maps for some infrastructure then tried to use the Inkscape to define the x,y for each needed point. I want to re-construct the map with these needed points using JOSM editor but whenever I jump to the x,y I got it turns to NAN! Is there any hidden scaling process applied on the JOSM editor coordination system or the mistake is actually from Inkscape?


title: How to best execute the same query on many different vector layers?

text: I have some vector layers in my project and I need to separate the polygones by area (I need a copy of all shapes > 2ha). I know how to do this for each separate layer (query) but is the a tool to do this for all my layers in one step?


title: OSGB36 referenced PNG to Google Earth

text: I am creating a PNG that is referenced to the OSGB36 datum (1 pixel per 50m easting/northing that is colored according to the result of some calculation code) I want to display this on Google Earth using KML. But obviously I need to transform the image before I do this. I can manually use gdal_translate to create a TIF file then gdalwarp to convert the image but I want to achieve this in code (C++) not via external applications. I looked at the GDAL API but having no joy doing what I can easily do with the aforementioned GDAL utilities. http://wtp2.appspot.com/warpdemo.htm seems to doing something similar to what I want but having looked at the JavaScript I don't really understand how the affine transformation is being constructed. Any pointers on how to achieve this would be much appreciated.


title: definition query and mosaic dataset from gdb ArcMap 10.1 SP1

text: I have a Python AddIn Combobox to select a value from the drop-down list. This value changes the definition query of the layers in mxd. This works fine for "normal" feature classes, not for a mosaic dataset. On the Layer Properties dialog box the DefintionQuery tab is empty.               layer_lst = arcpy.mapping.ListLayers(arcpy.mapping.MapDocument("CURRENT"))          for layer in layer_lst:             if layer.name in ('dted_hillshade','dted_dem6x6') and layer.supports("DEFINITIONQUERY"):                layer.definitionQuery = "\"NAME\"=\'000E00N.DT2\'"           arcpy.RefreshActiveView()      Does anyone one know a workaround to set a correct Definition query for mosaic dataset?


title: How to obtain the value of a feature programatically, based on a coordinate

text: I have a point layer, and a polygon layer, and I wish to calculate the value of an attribute from the polygon layer at each point's location. Eg, find the area of the polygon which is found at each point, and write it to the point's attribute table: ![enter image description here](http://i.stack.imgur.com/pPNeo.png) One simple approach is to perform a spatial join \- but this creates a _new_ output point layer. I would prefer to update the _existing_ point layer. I could iterate through the points layer and:   1. obtain each point's OBJECTID   2. create a layer from the selected point, using the OID as the `Where clause`   3. perform a Select By Location, using the above layer as the `select_features`   4. iterate through the selected polygon(s) and write the Area value to the point Steps 2 and 3 seem a bit extraneous - **is there a programmatic way to obtain the value of a layer based solely on an XY coordinate?** This would be akin to using the Identify tool in ArcMap, whereby clicking on a location reveals the attributes of the layers at that location.


title: MapBox import from TileMill gives only 1 layer

text: This is my first time using MapBox and I'm trying to import a map from TileMill. The map has 11 layers, in TileMill, but when I import it directly to MapBox, it only seems to have a single layer. It still shows all of the layers, but if I run the following, it returns a single layer, which seems to have all of the data on:               mapbox.auto('map', 'MAP_NAME', function(map){             console.log(map.getLayers());     });      For the map functionality, I need to be able to switch the layers on/off via user interaction, so having everything in a single layer is a slight issue. Am I doing something wrong? I really hope that I don't have to export each of my TileMill layers individually, as this will take so much time.. Any help/advice would be much appreciated. Kind regards * * * EDIT After hours of searching, I've found this question on the MapBox support pages: http://support.mapbox.com/discussions/tilemill/2122-creating-a-batch- of-layers It looks like TileMill is unable to export the layers and keep them as separate layers. Instead I will probably have to export each layer individually, which is a bit of a pain, but oh well. If anyone has any better suggestion, please let me know :)


title: How to compute flow direction and flow accumulation with Qgis?

text: Any one who had made flow direction and flow accumulation on raster data for filled evaluation model i Qgis? Which tool and plugins are necessary, i haven't been able to find any guidelines on Google


title: How does a spatial database display maps through WMS?

text: If a spatial database is configured to display maps through WMS, is it always configured to display through TMS and WMTS also? Or is this something that must be configured on the server side separately?


title: Creating Vector features onload in Openlayers

text: Using openlayers and javascript I wish to create two vector layers and add a polygon to one of them and a circle with a centre point to the other My polygon will be in WKT and my circle will be a point with a radius (Either as a distance or converted into approx DMS First) I’ve seen this page http://openlayers.org/dev/examples/vector-formats.html but I need to it onload as the variables will be passed from an HTML form into a Perl script witch in tern writes the open layers This is as far as I’ve got               Var box = new OpenLayers.Format.WKT().read("POLYGON((1.3 52.1,1.4 52.1,1.4 52,1.3 52,1.3 52.1))”);      This fails error message is vector.div undefined do i need to create the layer first then add the feature? Also Can I get the style from GeoServer or do I need to set it here? Haven’t a clue how to create the other layer. Could some one give me and example of how to do this? By the way my base layer / co-ordinate system is WGS84 and so are the given co-ordinates. Thanx Holly **UPDATE STYLE CODE** If i wished to draw the new vector polygon as a green box with a black border would this work?               var Green_Box ={         fillColor: "#33CC00",         strokeColor: "#000000",         strokeWidth: 1          };     var vectorLayer = new OpenLayers.Layer.Vector("myPolygonLayer");          var format = new OpenLayers.Format.WKT({         'internalProjection': map.baseLayer.projection,         'externalProjection': new OpenLayers.Projection("EPSG:4326", {          'style': Green_box,           'renderers': renderer          });      note: was playing with this at work came home found the above but now unable to test it until after easter Thanx


title: Managing ArcGIS floating licenses

text: How do you manage your ArcGIS floating license pool? I have to field several calls a week, or sometimes a day, from staff wanting to be able to check out Spatial Analyst or ArcInfo but they can't because there are none available. I've a little script I run to get a list of who's got what, and then need to either make phone calls to find out if Sam or Ellen really is still using SA or pass on the list of names to the caller so they can do the leg work. Better than half the time the user has simply forgotten to downgrade their license level, or close ArcMap/Catalog after they've done what they needed to do. This is monkey work that really should be handled by a computer. I've not found anything that really works for us yet. What do you do?


title: Has (ESRI) TIN been superseded by Terrain Dataset?

text: I've had version 10 for a few months but it wasn't until today that I really tested the 3D Analyst extension. (Other then visualizing data) I already noticed a lot of changes; a number of tools have been re-named or re-worked all together which also impacts my usual work-flow. I will not list all the details but the question is whether the 'TIN format' has been superseded by the improved 'Terrain Dataset'? Should I be using terrain datasets now even for simple surfaces? _Example: Hardclip and Softclip functions do now work in version 10 (as far as I can tell) and I noticed that defining the edges of a TIN dataset should be accomplished by using the 'Deliniate TIN Data Area' tool instead. However, to do this Average Point Spacing is required. Strangely this needs to be obtained from the input XYZ file not from the TIN itself. Alternatively, knowledge of the data is needed to take some manual measurements and to estimate the average spacing. This information is also needed to create a Terrain Dataset so it might be easier to just migrate to Terrain Datasets all together. But, di functions such as 'Extrude Between' support Terrain Datasets? TIN not processed with 'Delineate TIN Data Area' yields very strange contour results so it looks like things have to be done this way._


title: How to use the SLD Filter "Difference"

text: I have a postgis table with polygon geometries. I would like to create an sld which first does an inside buffer, and then a difference between the buffer and the original geometry. This is basically like cutting a hole out of the polygon....ie first buffer (say...50 meters) and then cut this buffered polygon out of the original polygon. I can´t seem to get my head around the syntax of using the sld filter explained here http://docs.geoserver.org/stable/en/user/filter/function_reference.html               <Intersects>     <PropertyName>GEOMETRY</PropertyName>     <Literal>     <gml:Point>     <gml:coordinates>1 1</gml:coordinates>     </gml:Point>     </Literal>     </Intersects>      This is an intersect function which only displays the points which intersect 1,1. I guess a DIFFERENCE function with a buffer would have to be somehow nested...but I don´t know if this is possible. If anyone can help. i´d be really grateful, yours, Rob


title: How to get the radius of a "circle" in Openlayers

text: How do you get the radius of a circle in openlayers? I have searched quite a bit and cannot find any resource for this. please help. Here is my code but I want the radius or circumference of the circle and not the area.                        // The Drag function is now made and called              // Add Drag          drag = new OpenLayers.Control.DragFeature(polygonLayer, {          autoActivate: true,          onComplete: displayArea           });                   function displayArea(feature){         var area = feature.geometry.getArea();              alert(area);              }


title: Is there website with list of common QA/QC errors?

text: As I am working on reviewing my soils spatial data, and I am doing my QA/QC I placed a point layer to check for errors. I add the field column to mark the error and state the error. I recently read the articles that came from ESRI on "Starting a Quality Assurance Program", " **QA/AC for GIS Data: Initial Quality Control Checks** " and "QA/AC for GIS Data: Recording and Tracking Errors" transcripts. Is there a website of where there are potential list of popular errors that I can take a look at or samples such as pictures of the error?


title: Openlayers Vector Layer Polygons not displaying properly with OSM

text: So I have an Openlayers map displaying Acetate tiles in OSM, and I'm drawing polygon regions on a vector layer to represent the countries of the world. This works fine for the most part, however, there seems to be a problem with where the vector layer ends and it not repeating the regions. For example, here is the zoomed out view: ![enter image description here](http://i.stack.imgur.com/dH2uW.png) As you can see, the polygon ends/begins on the east side of Russia near Alaska. This looks okay in this view, but if you start navigating around, it starts to get confusing. As you can see in these two screenshots, parts of Europe or North America aren't showing even though I've drawn polygons over those regions. As you scroll to the left and right these regions will hide and show: ![enter image description here](http://i.stack.imgur.com/D6naY.png) ![enter image description here](http://i.stack.imgur.com/1ORlU.png) I'd appreciate any help or experience anyone might have for this. It's really preventing me from being able to use OSM layers in general. Thanks in advance!


title: How to change the pixel value of a raster dataset which overlaps a polygon featured shapefile in ArcGIS

text: I have a raster data of 1992 and a 'shapefile' of Los Angeles county. I want to reclassify the pixel value of the raster data set to 'no data' or zero in the region where the raster and the 'shapefile' overlaps. I'm using ArcGIS 10.1. I tried using spatial analyst tool> 'reclass'. But I'm not getting the desired result.


title: Is it possible to install Geoserver on Zentyal?

text: We want to setup a small WebGIS environment based on Geoserver/PostGIS or even the OpenGeoSuite if possible. Our Server runs on Zentyal. Is it possible to install Geoserver and PostGIS on Zentyal and if so is there any documentation available? Or what would be an easy to operate platform so that we can create our WebGIS (we do not have much experience in running web servers though).


title: How to perform a buffer analysis in PostGIS?

text: Need to Implement Spatial Analysis in Postgresql. Can Any one guide me to accomplish the spatial analysis eg) 2 km buffer for road network layer.


title: Stitch mapbox tiles

text: I have customized mapbox tiles and i need to print it on A2 size paper on high zoom level at around scale of 500 to 1000. I am thinking of stitching the adjacent tiles together to form a single big map. How can i do it?


title: Creating map documents based on similar feature class selection

text: I wondering if something like this is possible. I would like to create a PDF output using a pre-established map template. The tricky part is I want to create maps in batch by adding (what will usually be 2)feature classes as layers to a data frame in the map document. These feature classes have similar names, the only difference is one of the names is preceded by "buffer_". The feature classes will then be symbolized. I am very new to arcpy mapping and seems like this may be possible however, I am stumped as to how to do this. The limited code I have so far (which doesn't run properly) looks as follows:               import arcpy, os, fnmatch          from arcpy import env               mapTemplate = arcpy.mapping.MapDocument(r"template location")     try:     df = arcpy.mapping.ListDataFrames(mapTemplate)[1]     print df     arcpy.env.workspace = r"file geodatabase"     fc = arcpy.ListFeatureClasses()     for fcs in fc:         name = fcs.getValue().replace("Buffer_","")         for i in os.listdir("file geodatabase"):             if fnmatch.fnmatch(i, name):                     arcpy.MakeFeatureLayer_management(fcs, "fc_layer")                 layer = arcpy.mapping.Layer("fc_layer")                 arcpy.mapping.AddLayer(df, layer + fcs, "AUTO_ARRANGE")                 mapTemplate.save()          except Exception, e:     import traceback, sys     tb = sys.exc_info()[2]     print "Line %i" % tb.tb_lineno     print e.message      I know this is no where close but I am having trouble even using the .getValue statement for the feature classes. Thanks for any suggestions or help you can provide.


title: Is there a dissolve / ST_Union function that will close gaps between features?

text: I've been reading a number of related threads about ST_Union, ST_SnapToGrid and ST_Dump but I haven't been able to solve my problem. The problem is I am trying to merge Tiger/line census tracts that have been simplified but I get gaps where the tracts aren't flush. I simplified the tracts with ST_SimplifyPreserveTopology(geom, .0003) and I'm running ST_Union(ST_SnapToGrid(geom, .00001)) but I still get gaps. I've also tried using ST_SnapToGrid around of the initial simplification but I don't see a difference. I've also tried wrapping ST_Dump around the Union but I don't see a difference there either. I thought ST_ExteriorRing was promising but my GROUP BY creates three concentric polygons (doughnuts) and ST_ExteriorRing seems to create three overlapping circles. Unless I'm doing something wrong. I'm outputting my query as geojson and putting that on a leaflet map. Here is what those gaps look like at different zoom levels. ![enter image description here](http://i.stack.imgur.com/kn1yD.png) ![enter image description here](http://i.stack.imgur.com/qCRIL.png) ![enter image description here](http://i.stack.imgur.com/qTiPb.png) If anyone has any ideas on making a gapless polygon of census tracts under 80mb I'm all ears.


title: Converting Easting, Northing, and Elevation to Station and Elevation

text: How can I convert x,y,z (easting, northing and elevation) data into station and elevation? I am trying to input the data into HEC-RAS, which only takes station and elevation.


title: Using Python to parse an XML containing GML tags

text: I am trying to write a python script which pulls GML tags out of an XML file and formats them into WKT for inserting into a PostGIS database. I have been successful in doing so for an XML containing a single part polygon using the follow code:                   rootElement = ET.parse("GMLExample_Polygon.xml").getroot()         wkt = ""         for subelement in rootElement.getiterator():             for subsub in subelement:                 if subsub.tag == "{http://www.opengis.net/gml}X":                     x = subsub.text                 if subsub.tag == "{http://www.opengis.net/gml}Y":                     y = subsub.text                     point_for_pol = "%s %s, " % (x, y)                     wkt += point_for_pol         wkt = wkt[:-2]      This code clearly won't work for multipolygons. I am unsure how to access the geometry for each polygon tag ("gml:Polygon srsName="BNG") separately and pull only the geometry nested under it. I am trying to use ElementTree, not sure if this is the best module to use? The XML is structured as follows:               <Order xsi:noNamespaceSchemaLocation="http://lalala.com/xml_polygon_order.xsd">         <OrderRequest>             <CustomerReference>999998</CustomerReference>             <SiteAddress>                 <Premise>456</Premise>                 <Street>long street</Street>                 <Locality/>                 <Town>London</Town>                 <County>London</County>                 <PostCode>PN1 1PN</PostCode>             </SiteAddress>             <SiteGeography>                 <gml:Polygon srsName="BNG">                     <gml:outerBoundaryIs>                         <gml:LinearRing>                             <gml:coord>                                 <gml:X>452847.6009</gml:X>                                 <gml:Y>18596.0496</gml:Y>                             </gml:coord>                             <gml:coord>                                 <gml:X>415847.6009</gml:X>                                 <gml:Y>184596.0496</gml:Y>                             </gml:coord>                             <gml:coord>                                 <gml:X>415847.6009</gml:X>                                 <gml:Y>184596.0496</gml:Y>                             </gml:coord>                         </gml:LinearRing>                     </gml:outerBoundaryIs>                 </gml:Polygon>                 <gml:Polygon srsName="BNG">                     <gml:outerBoundaryIs>                         <gml:LinearRing>                             <gml:coord>                                 <gml:X>452847.6009</gml:X>                                 <gml:Y>18596.0496</gml:Y>                             </gml:coord>                             <gml:coord>                                 <gml:X>415847.6009</gml:X>                                 <gml:Y>184596.0496</gml:Y>                             </gml:coord>                             <gml:coord>                                 <gml:X>415847.6009</gml:X>                                 <gml:Y>184596.0496</gml:Y>                             </gml:coord>                         </gml:LinearRing>                     </gml:outerBoundaryIs>                 </gml:Polygon>             </SiteGeography>         </OrderRequest>     </Order>      Thanks for any help.


title: PostGIS installation on Ubuntu 10.12 (Amazon Services)

text: On Ubuntu 10.12 (AMI on Amazon), I use `aptitude` to install Postgresql and PostGis. On terminal running psql interactive prompt, I type `CREATE EXTENSION postgis` and ERROR: could not open extension control > file "/usr/share/postgresql/9.1/extension/postgis.control": No such file or > directory Is there something I forgot to install?