title: How to merge linestrings which are connected with each other?

text: I would like to join linestrings which are connected to each other. The preferred output is a longer linestring based on all joined single linestings! The table that holds my single linestrings is called “traffic_roads_temp”. Each linestring has the attribute ref. Ref describes in my table the affiliation to a certain motorway or road. As you can see in the picture below the motorway A 2 and A 7 could be easily joined by using something like this:               select ref, st_linemerge(st_collect(way)) from traffic_roads_temp group by ref      One of the problem is, that the output seems to be a multilinestring and not a linestring. The main problem is the motorway A 39. It consists out of two separated road segments. Therefor I would like to generate two linestrings of the A 39 --> A 39.1 and A 39.2 All other motorways could be stored in one linestring per motorway. Maybe somebody of the experts in this forum could help me to solve this problem(s):   1. Generate long linestrings from single smaller linestring. (No multilinestring)   2. I case of the motorway A 39 which consists out of two spread road parts – I would like to generate something like a series: A 39.1 and A 39.2 Problem-Sketch: ![enter image description here](http://i.stack.imgur.com/7y3JU.jpg)


title: Need to delete all but one feature from a set of features with the same ID, keeping the one with the largest area

text: I have a large polygon layer in which most of the polygons have a unique name in a text field. Of the hundreds that aren't unique, there will be 2-4 polygons with the same name but different geometries. I need to keep one of those polygons in each set of duplicates, the one with the largest area, and delete the rest. Since the geometries are different I'm guessing I can't use ArcGIS' built-in duplicate finder and will need an SQL statement to do what I need but I'm far from proficient with SQL.


title: How to create a profile with profile points at discrete altitude intervalls, e.g. each 10 m

text: In both SAGA and QGIS theres a profile-from-line-function that does a nice job of creating profiles. But there's no way to control the altitude spacing. Any ideas for workflows that would allow me to achieve a profile (river as line-shape on a DEM-layer), with individual profile-points situated only at discrete altitude-intervalls of 10 m ? Of course profile points will need to contain information on segment-length and altidude... Any help appreciated!


title: In OpenLayers displaying two images at the same time

text: Within OpenLayers, I have two images, both jpg with world files, and each 1440 x 900 px. The two images are geographically located next to each other. Is there a way to display both images at the same time. I can make an image layer for each and use the Layer Selector to toggle between them, but I cannot figure out how to display both images together. From my reading it appears that an image layer is a base layer, and since two base layers cannot be active at the same time, I can only have one or the other active. thanks


title: Using QGIS, how can I add a bounding box attribute?

text: I have a shapefile where I am exporting the features to GeoJSON objects with ogr2ogr based on a simple where clause. One thing that I would like to be included in the GeoJSON object is the 'bbox' member (outlined here) , is it possible to add this as an attribute to the shapefile using QGIS? I've done something similar with centroids and added the x/y as separate attributes. Are there any other ways to programmatically add this to my geojson files?


title: Change slopes derived from DEM

text: I have a DEM for a region over which I want to simulate an ecological process. I would like to run several simulations for the same region but I want to alter the topography for the simulations. Most important, I would like to alter the slope (and probably aspect) in various ways. I am working in ArcGIS and I extracted the slope from the DEM but I have not found any way to manipulate the slope or even access the slope values with their coordinates. Running the process requires several other layers so I would like to remain within the parameters (coordinates, datum, ellipsoid, etc.) of the original DEM. Is there a way I can alter the slope output, which is currently a raster? Could I, for example, make the whole region 30% slope with a south aspect? Is there some other way to generate custom slope files that will be consistent with the other layers? I am using an ArcGRID DEM from the NED. Perhaps a different starting point is more appropriate, such as a contour map? Thank you.


title: Where can I publish my paper for free?

text: Is there any magazine (or some other such place) where university students can publish a GIS/Geo related article freely (in English or French)?


title: Making spatial clusters by direct manipulation of raster pixel values using R

text: I think this is an overambitious million dollar question, but I'm always optimistic when I pose a question even though I feel like I left no stone unturned! I've processed a raster layer with pixel values ranging between 1 & 8 (see here). A cursory glance reveals that, there's a good tendency of clustering in different parts of the heterogeneous raster band, occasionally intruded by unwanted unlike pixel values. My goal is to make spatial clusters with the following characteristics-   1. Every spatial cluster will represent only one pixel value i.e. all the minor intruding pixel values will be converted to the prominent pixel value surrounding it;   2. There can be more than one cluster with the same pixel value, but has to be spatially well-separated;   3. The clusters can be of any size &/or shape. Here you can see a few clustering example zones drawn by hand to show tentatively how I want them to be classified. I have searched the 'raster' package of R, but failed to discover anything relevant. A painstaking solution to such problems is digitizing, which, in many ways, is unprofessional, especially when someone has to deal with similar situations over and over again. I'll highly appreciate your suggestions/help.


title: Building CartoDB from source using updated dependencies on Ubuntu 13.10

text: I am attempting to build CartoDB from source on an Amazon VM for the first time in my life. For purposes of sanity, I want to use the same instance/database of postgres for both CartoDB and all of my other application data. After looking at the readme on github, I noticed that the dependencies were ridiculously out of date; consequently, I will need to make the following changes in dependencies:               Ubuntu 10.04 --> Ubuntu 13.10     Postgres 9.1.x --> Postgres 9.3.x     GEOS 3.3.4 --> GEOS 3.4.x     GDAL 1.9.0 --> GDAL 1.10.x     PostGIS 2.0.x --> PostGIS 2.2.x      If I am to do the switch, what special configurations will be necessary to get my setup to work. I plan to build all of the replacements from source. Why can I not just use the dependencies stated in the readme?   * Excessive amount of invalid topology errors when performing heavy geoprocessing on large multipolygon datasets. If I was just performing simple st_intersects() operations and using high quality data, (like TIGER) this would not be an issue. For me though, this is unfortunately not the case. I am processing ArcGIS-created data, produced by local government entities. To make matters worse,I am performing invalidTopologyError-spewing operations like st_intersection() and st_union(). Local GIS data often contains massive amounts of error -which is ignorned because ArcGIS operations are still able to be performed without consequence. Furthermore, the datasets I am working with are massive and so I cannot just manually fix individual polygons -even if postgis operations did let you know which features produced errors.   * In my experience, st_makevalid() before 3.4.x actually produces geometry that is "worse" than the issues one intends to fix by running the function!   * The entire Postgis ecosystem is under rapid development and has many bugs that directly affect my ability to perform certain operations on my data. With each release, it seems I am usually able to do something new that radically simplifies my GIS processing workflow.   * I want to drastically reduce the chances that an invalidTopologyError will wreak havoc on a "live" database/map.   * Ubuntu 10.04 is just excessively old -I wasn't even a programmer when this was first released!   * I just like to keep things as current as possible to avoid "well we fixed this in later versions, just upgrade!" issues. Any links wikis/blogs or fabric scripts for similar installations would be much appreciated!


title: How to check for overlapping polygons in Oracle?

text: I have a table 1 which has a fields like store number and geometry and it just has one record in it. Now I want to check for this store number in table 2 and identify if there are any polygons overlapping to this particular store number polygon and insert them into the table 3. Below is sql block I am trying to use.               Insert into table 3          select a.store_id,a.store_number,a.client_id,a.geometry     from  table 2 a,table 1 b     where a.client_id=b.client_id     and SDO_RELATE(a.Geometry, (select Geometry from table 1  where store_id          = 34746),'mask=anyinteract') = 'TRUE';      But it just returns 1 field in the new table for any store id I select.


title: Which world map projection allows comparing countries by shape and size?

text: The Mercator projection increases scale along with the latitude. Greenland seems larger than Australia, when in fact it is much smaller. The equal-area projections however stretch shapes away from the Equator. I suppose that there exist no projection that preserves size and shape at the same time. But for the purpose of comparing countries it is in fact not needed to preserve any properties exactly. The distortions should be only roughly the same in any point of the map. What is the map projection that accomplishes it most closely? ![Comparison between Greenland and Australia](http://i.stack.imgur.com/vxcVn.png)


title: A problem with ArcGIS network analyst making paths and roads work together

text: Working in Arc GIS 10 .0 service pack 5, network analyst extension, Productivity Suite 2.1 service pack 7, on Windows 7. I am trying to get the Ordnance survey ITN urban paths layer to work with OS ITN roads to model pedestrian journeys. I've had a ton of problems doing this mainly related to the sofware that unpacks the OS raw data, but I think (?) it finally unpacked it OK and my problem is in Network Analyst in Arc. I've got threads on a bunch of forums and I think I'm inching towards a soloution. I need nearest facility and service areas that are based on connections across both paths and roads in a network. I had a network that would do solves but only on paths or roads but no connectivity between them (the connectivity properties were fine though). From other advice I got I found there were two problems here, firstly a bug in Productivty Suite which the service pack (and a reinstall) got around. Secondly I'd not integrated the two layers - so I did this using the integrate tool without crashing or errors, although I'm not sure I've done it right - I just integrated the path links and road links - not sure if I need to select all of the nodes as well and integrate the lot? Assuming I have done this correctly, I now try a simple route solve to test the data that have been unpacked and integrated and I get an error message that says it is "unable to create a network anlalysis layer because the network data set has no cost attributes". Not sure where my cost attributes went or what to do about this. Incidentally I'm not doing anything very sophisticated with costs, I simply want a bunch of nearest facilities and service areas based on walk distances in metres - no parameters use of hierarchies or anything. BTW I've got the technical paper from the OS on using Connecting Links in Urban Paths. Has anyone out there made these data work together? - if so I'd really welcome a quick description of the work processes you used. Many thanks.


title: How to import coordinate data from excel into QGIS?

text: I have an excel file containing data collected over many years as latitude and longitude coordinates for archaeological sites - how can I import it into QGIS as a new layer?


Is there a way to select what to import from planet-latest.osm.bz2 to database? I want to do something like :               osm2pgsql ...  --place='city' --admin_level='2'      My goal is to use only cities and countries im my project ( maybe towns ). I can download many databases with cities and countries shapes from the world, but I think OSM is more complete and if I decide to use other things is just import again. I just try import all full planet data and then SELECT and INSERT in other database using SQL filters, but its too time-consuming ( and non-professional ). Thanks.


title: Arc Scene vs Sketch up

text: I am very familiar with Arc Map but have not really used Arc Scene. (I'm on 9.4) I am wanting to create an house model for remodeling and am wondering if it would be easier in Arc Scene or Google Sketchup? In addition, I'm also wondering if you just need to create the 3D shapefile in Arc Map & then add it into Scene? I didn't see any options to draw a shapefile in Scene. Thanks for helping!


title: How to style a WMS layer?

text: I also posted this question on stackoverflow. * * * I successfully overlayed a WMS layer in google maps v3, however, as the information on tiles is black on transparent, it is not well seen on dark background (like satellite map), see some tile for example: ![http://geoportal2.uhul.cz/wms_oprl/?SERVICE=WMS&REQUEST=GetMap&SERVICE=WMS&VERSION=1.1.1&LAYERS=HMLCR&FORMAT=image/png;%20mode=24bit&FGCOLOR=0xFF0000&TRANSPARENT=TRUE&SRS=EPSG:4326&BBOX=16.58935546875,49.37522008143603,16.600341796875,49.38237278700955&WIDTH=256&HEIGHT=256&STYLES=](http://i.stack.imgur.com/aPkKz.png) ( **This** was the WMS link to retrieve that tile) **Question: how to modify the above WMS request to change the foreground color (currently black) to some custom color (e.g. red)?** In other words, how to style the layer? The server is apparently able to do it for this layer, since it is possible to do it via their web map application (which works in IE only), where you can select the color. See this map image for example: ![enter image description here](http://i.stack.imgur.com/xcWjE.png) ( **The following link** was used to retrieve the image - note that it contains scale and logo, so it's not a proper tile.) Unfortunatelly, this web application doesn't use WMS to get this styled map so I can't just copy the styling parameters to WMS request. **I must do the styling via the WMS request** (because this other request format is proprietary, retrieves whole map - not designed for tiles - and it doesn't seem to support WGS coordinates) - **how shall I do it?** I tried to:   1. look at the WMS documentation, especially version 1.1.1   2. look at the SLDs, but it seems pretty complex thing to grasp...    3. look at the GetCapabilites command output for the WMS server   4. Also, having look at DescribeLayer and GetStyles command outputs for my desired layer (HLMCR) I don't even know if this layer will support styling over WMS...  I got lost, I'd be grateful if you point me to the right direction - or information if it's even solvable in WMS (for this layer). ### "It's not possible" is also a useful answer for me! Thanks in advance.


title: Does it matter what webserver (Apache, IIS, ...) is used with Geoserver?

text: I want to develop a geoportal using GeoServer. I installed GeoServer and Apache and I think the connection between the two of them is done. Today my boss told me about IIS. what i want to know is if i develop geoportal with Apache it will work also in ISS ? what should i modify if i copy the project in ISS ? what are the configurations that i have to do in this case ?


title: Problem with matching a buffer in Openlayers and the same buffer in PostGIS query

text: I am using a buffer tool to create a buffer on my base map in Openlayers. In addition to creating and visualizing this buffer, I pass the center point and radius to a query. The query collects all features of a certain table which fall into this buffer, and shows them on the map. The problem is that in these two cases buffers are generated separately and are not exactly the same. This causes the query to collect less (not all) features inside the buffer. Below is an image to clarify the situation. You can see the buffer created in Openlayers in Orange color, as well as features inside it that are collected from PostGIS in black and gold colors (different features). ![the circular buffer in OpenLayers and the ellipsoid shape of results retrieved from PostGIS query](http://i.stack.imgur.com/qTRTB.jpg) Its easy to see how much difference is between these two buffers and the one that is generated by the query is more like an ellipsoid rather than circle. how can I solve this? The code for generating buffer in Openlayers:               var sides = 40;     var new_geom = OpenLayers.Geometry.Polygon.createGeodesicPolygon(centroid, radius, sides, 45, projection);      and I use the following WHERE clause inside my SELECT query:               WHERE ST_DWithin(ST_Transform(h.geom, 26918), (SELECT ST_Transform(ST_GeomFromText($center_buffer, 900913), 26918)), $radius_buffer)      more information: **_h_** is the alias of my table where I want to collect features that fall inside the circular buffer. and *center_buffer* and *radius_buffer* are the variables pass by OpenLayers (the same used for creating the buffer in OpenLayers). **UPDATE:** As mentioned by a forum member below, the city data is around hamburg and therefore I changed my SRID in my query from 26918 to 26931. With this, the problem of strange ellipsoid shape of my features inside buffer is solved but there is still a big difference between the buffer and the data retrieved from PostGIS. See image below: ![enter image description here](http://i.stack.imgur.com/kIYmr.jpg) Any further help/suggestion would be highly appreciated.


title: R - What is the purpose of .GAL lattice file?

text: Could someone please explain to me what the purpose of a .GAL lattice file is? I want to see if my data are spatially autocorrelated and I've been following Bivand (2013). I have loaded my polygon file of London postcodes. The response variable is broadband speed, and I have various independent variables including number of premises per postcode, number of broadband connections per postcode and whether superfast broadband has been enabled. I'm not sure what I need to do to generate the .GAL lattice. I can't find an explanation anywhere. Here is Bivand's code:               > NY8 <- readShapeSpatial("NY8_utm18")     > NY_nb <- read.gal("NY_nb.gal", region.id = row.names(NY8))      Thanks!


title: Database design: road topology in GIS

text: Is there a standard or a best practice way to store certain features about roads: ## Road directionality:   * **One way streets:** Roads going in one direction only   * **Center Turning lanes:** roads that exist between two lanes, that either lane can use to turn left or right such as this   * **Highway interchange Ramps and merge lanes** ## Road Functionality:   * Intersection layout (signalized or unsignalized):      * Incorporating the different allowed and disallowed patterns of an intersection into a db, such as:     * No-U turns     * Turn left on green (or not)     * green cycles and times     * Actuated versus non-actuated approaches in intersections     * Right of way rules: Some intersections might have different Right of Way rules than typical. Take for example a hilly road, where everyone must stop at the stop sign, except for the people who are traveling uphill. They do not have a stop sign, so all traffic must yield to them.


title: Census Block GEOid2 conversion to Latitude Longitude

text: My question is similar to this question. I have two different data files.               Data1.csv (4500 rows)     GEOid                       GEOid2              Total Population    Urban   Rural     1000000US220019603001020    220019603001020     72                  0       72               Data2.csv (7000 rows)     Latitude    Longitude   ADT     30.48103    -92.61743   234      I want to get GEOid2 for each point (latitude, longitude) which I can do manually by using this API. This task will be then tiresome. Is there any particular method by which I can use the list of latitude and longitude to get exact GEOid2 for each location point by using that API? Finally I want my table like this.               Data.csv     Latitude    Longitude   ADT GEOid2            Total Population   Urban  Rural     30.48103    -92.61743   234 220019603001020   72                 0      72


title: Intersection failing because of vertices of polygons

text: I've written some code to intersect features of one layer with another's, but one layer has polygons (the squares in the image) and the other has circles (not filled). The problem is that I'm using IPointCollection interface to get the features' points and I'm only getting the border vertices of the squares ![enter image description here](http://i.stack.imgur.com/hoA7g.jpg) I tried getting the convex hull of one single feature but I failed because to use the intersect method I still have to convert to a IPointCollection Here's the code I am using               // Get first layer's points     IGeometry multipoint = new MultipointClass();     multipoint.SpatialReference = m_firstLayerFirstfeatureIGeometry.SpatialReference;     IPointCollection multipointPoints = (IPointCollection)multipoint;          // Cycle all features of first layer and add them to the collection     foreach (DataRow m_dr in m_firstLayerfeatureGraphics.Rows)     {         // Takes this feature's geometry         ESRI.ArcGIS.ADF.Web.Geometry.Geometry adfFeature =             m_firstLayerfeatureGraphics.GeometryFromRow(m_dr) as ESRI.ArcGIS.ADF.Web.Geometry.Geometry;         // convert to a igeometry object         ESRI.ArcGIS.Geometry.IGeometry m_tempfeatureIGeometry =         ESRI.ArcGIS.ADF.Web.DataSources.ArcGISServer.Local.Converter.ToIGeometry(adfFeature, ctx);              IPointCollection mtempfet = (IPointCollection)m_tempfeatureIGeometry;              //Add copies of the polyline vertices to the multipoint.         multipointPoints.AddPointCollection((IPointCollection)mtempfet);      }               ESRI.ArcGIS.Geometry.ITopologicalOperator6 mtopo1 = (ESRI.ArcGIS.Geometry.ITopologicalOperator6)multipointPoints;               // Get second layer's points     IGeometry multipoint2 = new MultipointClass();     multipoint2.SpatialReference = m_masterLayerFirstfeatureIGeometry.SpatialReference;     IPointCollection multipointPoints2 = (IPointCollection)multipoint2;          // Cycle all features of first layer and add them to the collection     foreach (DataRow m_dr in m_masterLayerfeatureGraphics.Rows)     {         // Takes this feature's geometry         ESRI.ArcGIS.ADF.Web.Geometry.Geometry adfFeature =             m_firstLayerfeatureGraphics.GeometryFromRow(m_dr) as ESRI.ArcGIS.ADF.Web.Geometry.Geometry;         // convert to a igeometry object         ESRI.ArcGIS.Geometry.IGeometry m_tempfeatureIGeometry =         ESRI.ArcGIS.ADF.Web.DataSources.ArcGISServer.Local.Converter.ToIGeometry(adfFeature, ctx);              IPointCollection mtempfet = (IPointCollection)m_tempfeatureIGeometry;              //Add copies of the polyline vertices to the multipoint.         multipointPoints2.AddPointCollection(mtempfet);     }               ESRI.ArcGIS.Geometry.ITopologicalOperator6 mtopo2 = (ESRI.ArcGIS.Geometry.ITopologicalOperator6)multipointPoints2;                    // INTERSECTION     ESRI.ArcGIS.Geometry.IGeometry mpointCol = (ESRI.ArcGIS.Geometry.IGeometry)mtopo2.IntersectEx((IGeometry)mtopo1, false, esriGeometryDimension.esriGeometryNoDimension);               // Draw the result     DrawIGeometryOnMap(m_Map, mpointCol);


title: Provide 3 colors to a polygon

text: Is it possible to provide 3 different colors to a single polygon in arcgis server 10 using c#.net? If yes how? I am new to arcgis server. Thanks in advance VBD.


title: Force ESRI Silverlight Navigation control to adhere to tile cache zoom levels?

text: Is it possible to force the Silverlight Navigation control to stick to the zoom levels associated with a particular tiled map service? The map tiles don't look very good when the images are being stretched by Silverlight to a zoom level they were not intended for. Labels are hard to read, etc. This doesn't look so good: ![enter image description here](http://i.stack.imgur.com/hEtOF.png) This is a little better: ![enter image description here](http://i.stack.imgur.com/W3e6b.png)


title: GeospatialPDF javascript access

text: Using javascript in GeospatialPDF, is it possible to zoom in to an extent, say when the document is opened the first time ? To what extent can I use javascript to access the geospatial data? pan, zoom, turn-on/off layer ? From GDAL Geospatial format page: Create of PDF with some JavaScript :               gdal_translate -of PDF my.tif my.pdf -co JAVASCRIPT_FILE=script.js      where script.js is :               button = app.alert({cMsg: 'This file was generated by GDAL. Do you want to visit its         website ?', cTitle: 'Question', nIcon:2, nType:2});     if (button == 4) app.launchURL('http://gdal.org/');


title: Hibernate Spatial - 'Invalid endian flag value encountered' Exception

text: I'm trying to run a simple query in Hibernate Spatial 4.0 on PostgreSQL 9.3. I have a number of objects in a table with latitude/longitude values, and I'm trying to query objects that fall within a given radius of a particular latitude/longitude. The geometry values seem to be persisted without any problem, and are defined like this in my entity class:               @Column(columnDefinition = "Geometry", nullable = true)     @Type(type = "org.hibernate.spatial.GeometryType")     private Point coordinates = null;      I don't have any errors when persisting objects with the `coordinates` value set. However, when I run a query, I see the following Exception:               javax.servlet.ServletException: javax.servlet.ServletException: javax.ejb.EJBTransactionRolledbackException: org.hibernate.exception.GenericJDBCException: could not extract ResultSet          <snip />          org.postgresql.util.PSQLException: ERROR: Invalid endian flag value encountered.      The query I'm running looks like this:               Query query = this.entityManager             .createQuery(                     "SELECT v FROM MyEntity v WHERE within(v.coordinates, :filter) = true",                     MyEntity.class);     query.setParameter("filter", point);      I came across this question on StackOverflow that mentions the same error, but I'm declaring my `coordinates` property the same way that is mentioned in the answer and still get this error. For the record, I've tried using PostGIS 1.5.2 and PostGIS 2.1.0. I've also tried different version of my PostgreSQL JDBC driver, from 8.4 to 9.3. Regardless of the library version I still encounter this issue. Can anyone shed any light on what could be happening here? Is my query wrong? Is my property not defined correctly? Is there something else I should be trying? I'm completely stuck and at a loss for what could be the issue here. Any advice would be GREATLY appreciated.


title: Choosing web/mobile mapping API

text: We are building a spatial application targeted to laypeople which will involve viewing and editing vector geodata (currently just points, but linestrings and polygons in the future) with a raster underlay. We'll deploy both web and mobile (iPhone now, Android and perhaps others later) versions. The server is a custom app we are writing, and there are no ESRI products on the server side. My question, therefore, is: **How do we choose which client-side mapping toolkit to use?** I'm aware of the following options, are there others?   * Google Maps API or similar (Yahoo, MapQuest, etc.)   * OpenLayers (does it work on mobile browsers?)   * ESRI's web/mobile APIs We are particularly interested in the pros/cons of the ESRI APIs under this scenario. Our company does have some kind of relationship with ESRI, though I know nothing about the details (and our group currently has no involvement with ESRI or ESRI products).


title: How can I calculate the center point inside a polygon in ArcGIS 9.3?

text: I'm using the JavaScript API 1.6 on ArcGIS 9.3. I have a polygon geometry in an ArcGIS map, and I'm trying to find a way to get the point that lies in the exact center of the geometry. What is the best way to do this? Thanks!


title: Using ST_split to split a line feature using nearby points

text: I have a line shapefile and a point shapefile, and   * the line has just one segment ![enter image description here](http://i.stack.imgur.com/7SFxH.png) and its attribute table, ![enter image description here](http://i.stack.imgur.com/Nd1XM.png)   * the point shapefile has points near the line above, not on it ![enter image description here](http://i.stack.imgur.com/s5OKI.png) and the close look, ![enter image description here](http://i.stack.imgur.com/euTe6.png) **I want to use ST_split to split this line at locations which are nearest to the points** **I want to get the original line with more segments(because being split).** For example, find the location on the line, which is the nearest to the point, and split the line at this location(star). ![enter image description here](http://i.stack.imgur.com/curgz.png) I loaded this line shapefile into PostGIS and here's my SQL code in PostgreSQL,               select ST_AsText(ST_Split(ST_GeomFromText('LINESTRING(0 0, 247907.60 2746404.62, 200    200, 400 400)'),            ST_Line_Interpolate_Point(ST_GeomFromText('LINESTRING(0 0, 247907.60 2746404.62, 200 200, 400 400)'), 0.2)))      And I checked the table of this line, it wasn't being splited. Where did I make mistakes？ I am new to use ST_split, please give me any suggestion, thanks. I am using QGIS 2.2, PostgreSQL 9.2 and PostGIS 2.0.4 under Windows 8.1 x64. * * * Update#1 @simplexio, I used your code,               select ST_Line_SubString(ST_GeomFromText('LINESTRING(0 0, 247907.60 2746404.62, 200 200, 400 400)'), 0 , 0.200 ) as geom into split_line ;      and got a new table named split_line, ![enter image description here](http://i.stack.imgur.com/yhkwQ.png) But as I used the following code you posted,               SELECT ST_Line_SubString(line, 0, ST_Line_Locate_Point(l.line, p.point)) as from_start_geom,            ST_Line_SubString(l.line,ST_Line_Locate_Point(l.line, p.point), 1) to_end_geom, l.line_id, p.point_id FROM lines l , points p      WHERE l.line_id = 1 , p.point_id = 1      I got a syntax error, ![enter image description here](http://i.stack.imgur.com/tKghD.png) How to fix this and move on？ And where should I assign the line I want to split as input of st_split？


title: For each polygon, return yes/no value if it intersects another layer

text: I have a polygon grid overlaying several other polygon vectors. I wish to visit each polygon in the grid and ask yes/no if each of these layers fall within the grid cell or not. I can do this easily with a spatial query to select the appropriate cells, but I want to have this information returned as a new attribute column, where each of the grid cells has a yes/no (or 1/0) value accordingly. This seems simple but I cannot figure out how to do it. Thank you very much for any guidance


title: Get list of coordinates for points in a layer?

text: I've got a layer in **QGIS** that is comprised of points. Its attribute table doesn't have (show) the corresponding **x** and **y** coordinates for each point. Is there a way for me to extract a list of coordinates for those points? (ideally into a **CSV** , but not required) Also, for the exported list of coordinates (say, in a **CSV** file), how do I include the existing attribute table with it? Thanks. For your information, I am running **QGIS** on **Mac OS X 10.6.7**.


title: Exporting QGIS attribute table to excel

text: I have a million rows in the attribute table, with lat/lon columns that I want to export to Excel. Selecting all the rows causes QGIS to crash. Is there another way to do the export? The million rows are for a million points on the map. Can the lat/lng be extracted from the shape file using another method?


title: How to find polygons centroids?

text: > **Possible Duplicate:**   >  Get list of coordinates for points in a layer? Sorry for another basic question - my map is almost done but now my boss wants me to enter new outbreaks (that we don't have coordinates for) into a map that has animal population data for several provinces (one shapefile for each country). At this point all I have for these newer outbreaks is the province that the outbreak was in - my boss has said that I can input the coordinates (roughly) for each outbreak by finding the centroid. I've used ftools for this, I've been importing data for outbreaks from excel files (using a delimited text layer) - for the outbreaks without coordinates (for which I only have data telling me what province the outbreak was in) I presume I'm going to have to make an Excel/DBF file with these coordinates. My boss says that I can get these coordinates by finding the centroids. I've tried using "Polygon Centroids" via the ftools plugin, and have a new shapefile with points on where I presume the center of each province is. **What I'd ideally like is a list** (such as in the attribute table) next to each province (which are listen in the attribute table of the shapefile I'm working with) **with the coordinates for each centroid**. Is there any way to get this done? The only other thing I can imagine is writing down the coordinates of each centroid of each province manually.


title: How to make icon marker size variable depending on data value using CartoDB?

text: Is there any way in CartoDB where I can make the size of individual icon markers, visualized on a CartoDB map, variable and set according to its data value in a given data range? Similar to the CartoDB "Bubble" visualization but i would like to be doing this for other Icon markers other than circle markers. Anyone having any idea I am most grateful for any clue or maybe recommendation for other tool than CartoDB that can do this if CartoDB cannot do it.


title: How to Zoom to a FeatureLayer Using ArcGIS Javascript API

text: I am making a web application using the Javascript API and am trying to zoom to a feature layer from a row click in a dojo data grid. I have this working for a dynamic layer, but am having issues with feature layers. I am getting a Firebug error that says `selectedTaxLot is undefined`. Do you have any insight why this might be occuring?               //Zoom to the parcel when the user clicks a row      function onRowClickHandler(evt) {       if (searchType == "selControl2") {         var clickedTaxLotId = grid4.getItem(evt.rowIndex).POINT_NAME;         var selectedTaxLot;         alert(featureLayer.geometry);         var highlightSymbol = new esri.symbol.SimpleMarkerSymbol().setColor(new dojo.Color([25, 50, 225, 0.3]));         dojo.forEach(map.graphics.graphics, function (graphic) {           if ((graphic.attributes) && graphic.attributes.POINT_NAME === clickedTaxLotId) {             selectedTaxLot = graphic;             graphic.setSymbol(highlightSymbol);                  return;           }         });              if (selectedTaxLot.geometry.declaredClass == 'esri.geometry.Point') {           map.centerAndZoom(taxLotExtent, 11)           var sp = map.toScreen(selectedTaxLot.geometry);              } else {           var taxLotExtent = selectedTaxLot.geometry.getExtent();           var screenpoint = map.toScreen(selectedTaxLot.geometry.getExtent().getCenter());           var mappoint = map.toMap(screenpoint);           map.setExtent(taxLotExtent, true);           map.infoWindow.show(taxLotExtent.getCenter(), map.getInfoWindowAnchor(screenpoint));         }


title: Landsat8 View Imagery Service in ArcMap Layer Time Issue

text: I'm attempting to work with one of the newer ArcGIS Online subscription imagery services called Landsat 8 Views which allows you to view Landsat data for the US across several dates in 2013. I can get the imagery service to click thru the various dates in arcgis.com viewer but not in ArcMap 10.2 When I attempt to enable time on the Landsat 8 Views layer in ArcMap it removes the layer from even being visible. Any ideas what may be going on here and what may be wrong? It's a huge amount of data in the attribute table and possibly part of the problem. I would like to clip specific dates for small areas but I can only get a single date to show which I guess is the one displaying on top. The server address for the Landsat 8 Views is **here**.


title: How do you delete an in-memory Table View?

text: In a Python script, I'm cycling through thousands of Excel files and using arcpy.MakeTableView to create in memory table views from the first spreadhseet in each file. How do you delete the reference to the in-memory view? I've tried deleting the variable that stores the table name, but to no avail.               tblView = sheetName     arcpy.MakeTableView_management(excelSheet, tblView, .....)          ## Process the table here          del tblView      The reason for deleting the reference is that in some cases the sheet names are duplicated in the Excel files. If a table view has been created with the name "Sheet1", you can't create another table view with the same name. In addition, due to the number and size of the Excel files being processed, I'm concerned about an impact on performance if all of those table views are preserved through the life of the script.


title: Using individual bands from a multi-band image in ArcGIS 10 raster calculator

text: I'm trying to use individual bands from a multi-band TM image (IMG file) within the raster calculator in ArcGIS 10 (SP2/3). I can add individual bands to my MXD, but raster calculator will only use Band 1 regardless of how I reference the layers from the MXD. Using something like `"TM_Image.img - Layer_3" - 0` in the raster calculator will run, but will use Band 1. Using the full path to the image works correctly but is unwieldy for longer expressions/paths. Like `"X:\TM_Image.img\Layer_3" - 0` I think this worked in earlier versions of Arc 10, but no longer on SP 2 or 3. Thanks for any advice on syntax that I might be missing!


title: error while setting domain name in cartodb

text: Able to login with a username **dev** as               http://dev.localhost.lan:3000      But i tried for a domain name, i was not able to login. Edited the **app_config.yml** file and changed the **localhost.lan** instances with domain name. Created a new login user. But when i tries to login with this               http://<domian_name>:3000      it always shows error in the password field. Is there a way to check if the **app_config.yml** is configured correctly. Any other config files to be edited. Thanks in advance


title: Unsure what to do after running osm2pgsql

text: I must admit that I'm a noob when it comes to database administration, but I'm a little confused at the process of my getting my .osm.pbf file into tilemill. I've run the osm2pgsql process on a .osm.pbf file, it ran, and said that it was completed. I'm pretty sure that this file goes into PostGreSQL, but I'm unsure of how to access this. Maybe my understanding of the process is completely skewed? Not sure, but at this point I know that when I use "psql" in the terminal I'm able to use SQL commands, although I haven't set up any specific account information. Any help is greatly appreciated! Thanks


title: How to cut a line feature in QGIS 2.0?

text: I want to shorten a feature (a polyline representing a road) in QGIS 2.0. I tried the 'cut features'-tool that look like a pair of scissors. First I chose the right layer, and then clicked 'Toggle'. Then I selected the road and chose the cutting tool. But, when I selected it, my polyline "disappears"? I never got a chance to start cutting. I don't remember having any problems with this in QGIS 1.8. Is there a step that I am missing here? I really want to get this to work, without having to download QGIS 1.8 again.


title: Display plugin icon

text: I'm unable to setup the display of the toolbar icon for a plugin in QGIS 2.0. I have compiled the "resources.qrc" with the correct path and filename, and checked possible spelling errors in the code. In fact, the icon is displayed in the plugin manager but not on the toolbar or the dropdown menu (?). The plugin has been started using the plugin builder for 1.8 version, but works just fine. The plugin folder is linked to the qgis plugins folder by a symlink on a linux system. Thanks. Edit: my qrc file :               <RCC>         <qresource prefix="/plugins/ViewshedAnalysis" >             <file>icon.png</file>         </qresource>     </RCC>      and my code :               self.action = QAction(             QIcon(":/plugins/ViewshedAnalysis/icon.png"),             u"Viewshed", self.iface.mainWindow())     QObject.connect(self.action, SIGNAL("triggered()"), self.run)               # Add toolbar button and menu item     self.iface.addToolBarIcon(self.action)     self.iface.addPluginToMenu(u"&Viewshed Analysis", self.action)


title: Setting up qgis web client

text: I have a problem with setting up a qgis web client on remote server. I set it up on localhost and it runs smoothly, but when I done exactly the same on remote server it is just not working, even a default maps. Helloworld example is not showing up layers, and my project is working only when i exclude about 20 layers, and by the way all styles are crashed. I could not find an issue, and exacly the same projects and many more runs great on localhost. It is link to remote server: 185.25.148.67/qgis-web-client/site/index.html **EDIT:** I noticed that on localhost server sends POST requests and on remote server it is always a GET request. I think that could be the issue, since request to display all layers in GET method would be too long. But i still couldn't figure out how to enforce POST method. **2nd EDIT:** It is POST on remote server at the end, but it still doesn't work, here is link to the project with more layers: 185.25.148.67/qgis-web-client/site/qgiswebclient.html?map=/home/web/qgis-web- client/projects/rzgow/start.qgs


title: Update the layout excel file automatically when the attribute table chnages in arcmap

text: I am trying to put an excel table in arcmap layout where this table includes some statistics over one of the Features Attribute table. This Feature is going to be updated regularly and consequently the Excel layout should be updated as well. How can I connect this Excel table to the Feature Attribute to update the statistics automatically. I have tried to create a GDB table and summerise the Information there but it does not get updated when the Feature informaton changes.


title: Creating a custom attribute table in qgis print composer

text: is it possible to arrange header and content of an inserted attribute table in qgis print composer? I want to create a custom datasheet with a small map and listed feature information as follows:![datasheet with header and content aof an attribute table arranged side by side](http://i.stack.imgur.com/CEU8G.jpg) I thought to change header font into white (and insert a label for each attribute content) but apparently this is not possible in qgis 2.0.


title: How to find differences between shapefiles?

text: Every month I have to QA/QC some streets data for an entire county (over 47,000 records). The first step is to compare the two files. Currently, I'm using a tool that was created in house via VBA approx 5 years ago. It works compares the two files and reports back the differences based on a few factors (added records, deleted records, address changes, city changes, segment length/vertices changes). I then export these to individual shapefiles. Additionally, the tool works in `ArcGIS 9.3` but will no longer work in `ArcGIS 10.1` The tool works great, but it takes approximately an hour to complete. I've started to work on hopefully improving this tool to speed up the performance. I've looked into a variety of methods including the `Compare Feature Tool` and `Select by Location`. Both of these tools work significantly faster, however, they don't seem to capture everything that I need. The big issue I have with the `Compare Feature Tool` is that I cannot choose which field to compare on. It defaults to ObjectID when I need to compare by Segment_ID. There isn't an option to select that. Does anybody have a good solution or ideas on how to achieve a full compare like I've described? **UPDATE** For some reason, ArcGIS isn't recognizing the join that I'm attempting per RyanDalton's answer. But Taking the advice of a join I have figured out how to find the added records and deleted records differences in the two files by:   1. Joining the Previous Month shapefile to the Current Month shapefile via the Segment_ID field   2. Performing a definition query where Segment_ID IS NULL   3. Exporting that to a new shapefile (Added Features) I then reverse the joins and find the Deleted Features Still working on a way to find the other differences listed and then string them all together in a model. **UPDATE 2** I can find all records that have changed by performing a select by location records from one of the datasets that are identical to the other dataset. I then switch the selection and it gives me all the records that are not identical. I'll put it all in a model and hopefully it works just as well.


title: How to compare differences in two shapefiles?

text: I am a new user to Arcmap 10. I've been trying to figure out how to compare two polygon shapefiles. I need to figure out what the difference is from 2007 - 2013 (increase/decrease) in a couple of TMK maps. Any help would be appreciated :)


title: Choice of Cartographic Font

text: I am currently trying to choose suitable fonts for a map. A very time consuming experience - actually too time consuming as i´m not a trained typographer and will inevitably make all the classic mistakes! In order to save myself time, and probably many other GIS users who very probably make all the classic errors when choosing font types, does anyone have any SIMPLE guidelines regarding which type of fonts should be used for standard thematic maps. I am not talking about artistic fonts for special types of graphic, just simple clear easy to read fonts which work well together in different sizes and weights in the same map. My main problem at the moment is trying to choose a large bold clear font for the main point theme layer annotations, and a less-weighted font for the place names. I want to have a sans-serif for the point layer which displays the names of the points in a dominant concisive factual way, but want a fitting and complementary serif-font for the place names which is thinner and less dominant. If anyone has standard fonts which they use together for most of their work, I would be grateful for any advice,


title: Geocoding failure on concurrent requests with arcgis-10.0

text: I've created a small python synchronous geoprocessing script (ctagc) that runs on AGS. The script accepts a table (GPRecordSet) as an input parameter. The script then calls `arcpy.GeocodeAddresses_geocoding()` to submit the table to a specified geocoding service running on the same server. The script then generates an output feature class "`in_memory`" to send back to the caller. When my silverlight client submits multiple http requests (4 threads of 100 records) of JSON batches of data through the generated REST interface on the server, the script INconsistently fails on the same data being submitted. On different runs of the test data, different batches fail each time (and a different number fail). This happens with different geocoding services on the server. I think that there may be problems with the geocoding service accessing the single locator file. I've tried changing pooling and isolation parameters. Still crashes. Does anyone know have suggestions for handling multiple requests hitting a geocoding service? I thought ArcGIS server could handle thousands of requests, blah, blah per hour? System Info: Running AGS 10.03 and have installed geocoding patch Gis10sp3-SGIS-GGM-Patch.msp from 1/3/2012 on virtual Win 2008 R2. Pooling services, low isolation. Error message returned to client: # example 1               Error Executing Task. Error executing tool.: \u003cclass 'arcgisscripting.ExecuteError'\u003e: ERROR 000464: Cannot get exclusive schema lock.  Either being edited or in use by another application.\nFailed to execute (GeocodeAddresses).\n\nFailed to execute (ctagc).      # example error 2               Error Executing Task. Error executing tool.: \u003cclass 'arcgisscripting.ExecuteError'\u003e: ERROR 000010: Geocode addresses failed.\nFailed to execute (GeocodeAddresses).\n\nFailed to execute (ctagc).               Server Log File Messages:     <Msg time='2012-02-09T12:12:44' type='INFO3' code='20022' target='cta/ctagc.GPServerSync' methodName='GPServerSync.Execute.ctagc' machine='VAGS10B' process='20336' thread='3152' elapsed='3.02319'>Execute job j769cfe004d6c4152a5357f7a9c318f7b</Msg>     <Msg time='2012-02-09T12:12:44' type='ERROR' code='20010' target='cta/ctagc.GPServerSync' methodName='GPServerSync.CheckMessages' machine='VAGS10B' process='20336' thread='3152'>Executing (ctagc): ctagc "Record Set" 0 0 2 12 Start Time: Thu Feb 09 12:12:41 2012 Running script ctagc... \\VAGS10B\ArcGIS\cta\ctagc_ags_connection\cta\comp_parcels_streets.GeocodeServer <class 'arcgisscripting.ExecuteError'>: ERROR 000010: Geocode addresses failed. Failed to execute (GeocodeAddresses).  Failed to execute (ctagc). Failed at Thu Feb 09 12:12:44 2012 (Elapsed Time: 3.00 seconds)</Msg>     <Msg time='2012-02-09T12:12:44' type='ERROR' code='20010' target='cta/ctagc.GPServerSync' methodName='GPServerSync.CheckMessages' machine='VAGS10B' process='20336' thread='3152'>Error executing tool.: <class 'arcgisscripting.ExecuteError'>: ERROR 000010: Geocode addresses failed. Failed to execute (GeocodeAddresses).  Failed to execute (ctagc).</Msg>     <Msg time='2012-02-09T12:12:44' type='INFO3' code='20024' target='cta/ctagc.GPServerSync' methodName='GPServerSync.Save.ctagc' machine='VAGS10B' process='20336' thread='3152' elapsed='0.00056'>Save job j769cfe004d6c4152a5357f7a9c318f7b message type SOAP message size 534</Msg>


title: Determine size of screen/map to limit number of markers displayed

text: I am writing a JQuery Openlayers javascript web application that connects to a API, which exposes a million geo located points plus metrics and information about the points. One metric is a points importance, so the points can be ordered and limited by this metric. I can request from the API a limited amount of points within a bounding box. The application is to be mobile optimised, which means I need to detect the screen size, taking into account pixel density, and change the amount of points to be queried and displayed as markers to the user. The markers are similar in size and look to google maps api marker/pin icon. The user can tap a marker and display a call out. So for a iPhone 3g, 4 and 4S a limit of 20 would be fine, an iPad 50, but for a desktop it's possible that it should be related to the current size the user has chosen for the map. The application is to be responsive to layout and the user can choose how many information panels to show, so it's possible on the iPad the limit should decrease as more panels are "unfolded". In fact the map is secondary, and this will be "foldable" too. How do I determine the screen size of mobile/desktop devices, including taking into account retina displays (i.e. denser displays don't display more markers)? Can I also determine the current map display area too?


It's been awhile since I've dealt with optical imagery. I need to perform a land cover classification at mid-latitudes using several LANDSAT scenes. I've noticed that some online tools are still selling the imagery, but I was under the impression that the archive was now offered up at no cost. What is the best/easiest way to obtain temporal Landsat imagery?


title: Does this routable network include oneways information?

text: I successfully imported osm road data using osm2po. I visualized the routable road network using Qgis. The table of the layer includes the following attributes: id|osm|name|osm_source|osm_target|clazz|flags|source|target|km|kmh|cost|reverse_cost|x1|y1|x2|y2 Does this routable network include oneways information or do I need to further process the data in order to get this information?


title: Intensity/Bubble Map

text: So I have been tasked to create a visual map of case volume shipped to each region from each of our warehouses. I think the most effective way to visualize this data is to create an intensity (bubble) map based on total shipped volume to each city. I know in my head of what I want to see but not sure what program is best to visualize this data. I have access to Microsoft Map Point 2006. I was thinking maybe Google Fusion Tables could also translate this but I have never used that tool. Ideally, I was thinking if i can have a radio button that represents inbound (like stock transfer orders) /outbound orders (customer orders), then a drop down for the warehouse selection, and have a map automatically generate the intensity/bubble map, would be great. I currently have my raw data in excel, I can pivot the data with the warehouse as a filter, and sum of cases by city & state. Does anyone have any suggestions or recommendations of free software that can be used? Thank you!


title: Update Layer with python, error attribute renderer

text: I am attempting to automate symbology using python, and ArcMap 10.0. I am importing this script into a toolbox, which I run from arcmap Currently I am getting two errors: 1) LayerObject: Set attribute renderer does not exist. I am not sure what the problem is. 2) When I change true to false, Could not find replacement layer. Here is my code:               import arcpy          mxd = arcpy.mapping.MapDocument("CURRENT")          df = arcpy.mapping.ListDataFrames(mxd)[0]          updateLayer = arcpy.mapping.ListLayers(mxd, "*", df)[0]          sourceLayer = arcpy.mapping.Layer(r"C:\me\fun.lyr")               for lyr in updateLayer:              arcpy.mapping.UpdateLayer(df, updateLayer, sourceLayer, True)          #UpdateLayer ( data_frame, update_layer, source_layer, {symbology_only})


title: Converting NZMG (or NZTM) to latitude / longitude for use with R map library

text: I am a statistician with no background in GIS so apologies for the newbie question. We routinely use R for a range of statistical and graphic analysis and are interested in using its map library to superimpose statistical graphics onto a map of New Zealand. Drawing a map of New Zealand is easy, as is adding cities. But as far as I can tell to project more data onto the maps I need latitude and longitude information. I have a database of key locations of interest to us with grid references in NZMG or NZTM projections. I've found the technical instructions on converting to lat and long here, and conceivably could write code in R that applies this process. But I've also found various web calculators that will do this for a specific point, so there must be relatively accessible software that does this automatically (I need to do it for about 2500 locations). So, one version of my question is: how do I easily convert, in R or Excel, a list of NZMG or NZTM projections into latitude and longitude. An alternative version of the question is: if I don't really need to convert them, is there some way I don't understand that the map projection packages in R can automatically project these locations onto a map? Apologies again if I have missed some fundamental point. EDIT / ADDITION after @whuber's helpful link to an almost identical question Ok, so I've installed the proj4 library but yes I am having difficulty in specifying my proj4string. If my understanding of this page is correct the NZTM system is basically a universal transverse mercator based on WGS-84. If I understand this map correctly I should by in zone 60 (or 59, as they both cover New Zealand? but neither work anyway). And if I understand proj4 properly the code below should be close. One of those "ifs" must be wrong... 1781304 E 5485722 N is a "NZTM" coordinate in my database that should be a suburb of Wellington, in the south of the north island.               library(proj4)     library(maps)     library(mapproj)     proj4string <- "+proj=utm +zone=60 +south +ellps=WGS84 +datum=WGS84 +units=m +no_defs "     p <- project(c(1781304, 5485722), proj=proj4string, inverse=T) # should be wellington     map('nz')     points(p[1], p[2], cex=5, pch=19, col=2)     points(-p[1], p[2], cex=5, pch=19, col=2) # In case I've misunderstood the sign. Appears on map but in the sea


title: OpenLayers: Possible to show zoom level?

text: Been researching this for a while and nothing has come to fruition. Best I could find was:               OpenLayers.Control.ZoomStatus = OpenLayers.Class(OpenLayers.Control, {       autoActivate: true,       element: null     });      But 'ZoomStatus' isn't even mentioned in the documentation (maybe it is but can't seem to find it). Found it at this link: http://trac.osgeo.org/openlayers/attachment/ticket/3629/OpenLayers.Control.ZoomStatus.js So, if anyone can offer some insight as to how to display the zoom level/status in the browser, that would be greatly appreciated!


title: How do you specify the width of a column that has been extruded from a point in arcscene?

text: I've extruded a set of points based on a z variable but I want to increase their width so they're easier to see.


title: How to access data from a selected feature in ArcGIS 10?

text: First to describe my problem as I see it. I've been asked to design a tool that will take a selected features attributes and copy it out to an output table, with each successive selection and processing of the tool adding a new row to the formerly mentioned output table. I'm trying to work exclusively in Python since my VB knowledge is None (or perhaps Null?).   My current method has been to make a Layer View consisting only of the feature that the user has selected and then use a search cursor to snatch the data and populate the other table with use of an insert cursor. This seems clearly inefficient to me, but more appropriate methods have not made themselves clear to me. However, to make matters worse, it would seem that my Layer View is simply creating a copy of the original table because I don't have a method for singling out a unique identifying attribute to create a Layer View with 1 feature. A couple of questions, then. 1) Is it possible through python/arcpy to access the attributes of a currently selected feature?   2) If this is not possible, what are other methods that come to mind for performing the task of extracting data from one feature class and using it to populate fields in a separate table?


title: Running ArcGIS 10.0 Under Virtualenv

text: I am working on a Python package that has a mixture of command line tools and ArcToolbox tools. For Python development it is really useful to use VirtualEnv, especially when working with installers. Is there a way to have either ArcMap or ArcCatalog recognize a current VirtualEnv session in Python, so that when a custom tools is executed it is using the VirtualEnv Python paths and packages instead of the default Python paths and packages at c:\Python26\ArcGIS10.0?


title: How to export data from ArcGis to .txt?

text: I have a file-geodatbase,it is a road network of a city. Now I want to export the data into .txt file for map matching, I have installed ArcGis for Desktop and not used ArcGis before, what should I do next? open the data with ArcMap ![open the data with ArcMap](http://i.stack.imgur.com/baPR9.jpg) txt format ![expect like this](http://i.stack.imgur.com/7ynu9.jpg) I am completely new to GIS filed, thx for any help!


> **Possible Duplicate:**   >  Shapefiles to Text What is the process of converting geodata in ArcMap 10 to WKT format? I am not a programmer so much, but will learn if needed. I have a set of shapefiles and need to convert them to WKT format. Please advise on the process required to do this. Many thanks


title: Extract Points from a Shapefile

text: > **Possible Duplicate:**   >  Shapefiles to Text I have several shapefiles from which I need to extract all of the points, with all of their attributes, including position coordinates. I only have access to opensource solutions, but can use whatever would be quickest/easiest, and would not be adverse to writing a little code if necessary. What would be the best way to go about this? Ideally I'd like the output to be a CSV.


title: Delete a feature data set in SDE 10 programmatically

text: Is there a way to delete a feature data set and all of its feature classes programmatically either by using custom code or pre-existing command line tools? There is a tool provided by SDE called sdetable.exe but i'm not sure if this will do the trick. My feature data sets are setup in ArcSDE via scripts which call a custom executable that imports XML workspaces. I'd like a way to delete the feature data sets that the XML workspaces import because when I re-run the scripts I get things like this: Underlying DBMS error [ORA-00972: identifier is too long (VITD.Surface_Drainage_Channel_Area_1)] The '_1' is appended because there is already a feature class named Surface_Drainage_Channel_Area. So I'd like to have my scripts first drop the VITD feature data set and all of its feature classes before importing my XML workspace XML document that creates it.


title: Is there anyway to modify thickness & color of a selected polygon?

text: QGIS - version 1.8.0. Is there anyway to modify the thickness and color of a selected polygon (Select Single Feature)?


title: How to calculate the "depth" of a linestring using postgis

text: I have linestring features, which look like bent linestrings, hemicycles or convex or concave linestrings. In the moment I can select the distance between the startpoint and endpoint of each feature. Now I want to calculate the vertical (orthogonal) distance between a) the imaginary line between startpoint and endpoint b) and the most distant point of the linestring Like the maximum orthogonal distance between the deepest point in a hole referring to a straight surface. How can I calculate this with postgis? Here is a picture: ![enter image description here](http://i.stack.imgur.com/f2de9.png)


title: How to have a drop down list for feature editing (attributes) in Quantum GIS?

text: I'm editing a lot of polygons of a shapefile in QGIS and i need to classify them, so i have to write the classes a repetedly a lot of times. In ArcMap there is an option to have domains set for the fields. How do i do this in QGIS? Thanks


title: How can I use jp2 aerials photos in QGIS?

text: I have previously been able to add raster data in the jp2 format to QGIS. I am able to do so on 1.8 installed on my laptop. Unfortunately when I attempt to do this on my desktop, it claims that the file type is unsupported. I installed using the OsGeo installer. I think I may have missed a setting on the advanced install?


title: How to change standard button bitmap of esri tool/command in ArcEngine 10

text: I'd like to use some of the standard 'out of the box' esri tools e.g. Measure Tool in an ArcEngine app, but I'd like to change the default bitmap of the tool button. Any suggestions would be gratefully received.


title: Fastest spatial storage format?

text: I am wondering what storage method will result in the fastest reading of the map vectors for rendering. SHP? PostGres? SQLite? (They do not change often and I do not need spatial functions for these vectors).


title: How to "Merge Selected Features" with python?

text: I have been looking for the answer to this question for some time now, but can't seem to find it! My problem is straight forward: I have one layer It contains lots of features (only polygons), say countrys I want to merge some features together. Using python. I know that I can select features with the mouse and hit the "Merge selected features"-button, but that is to slow. I can use python to select the features that i want, but how can i merge the selected features from python? (the features don't have a "common field" or something like that, what features are to be merged will be decided by in-data) Help is greatly appreciated!


title: Reverse Vector Layer Feature order

text: I have a vector layer where some features are found entirely within other features and therefore I can't select that feature because the other feature is on top of it. Is there a way to reverse the order of the features of a vector layer after they have already been loaded? This will likely solve about 99% of issues that may occur with my mouseover popup. **Edit to add code:** I'm trying to do this on demand after the layer is already loaded.               var refreshStrategy = new OpenLayers.Strategy.Refresh( {         interval : 60 * 1000       });        var vLayer = new OpenLayers.Layer.Vector("Hazards with Population",           {             projection : "EPSG:4326",             strategies : [new OpenLayers.Strategy.Fixed(), refreshStrategy],             protocol : new OpenLayers.Protocol.HTTP(             {                         url : "./getFeatures.php",                             format : new OpenLayers.Format.GeoJSON(),               rendererOptions : {                 zIndexing : true               }             })           });


title: Looking for Alternatives to Google gmaps utility widget for ArcGIS JSAPI API

text: I have been using https://code.google.com/p/gmaps-utility-gis/ as a solution to displaying Google imagery as a base layer on a ESRI JSAPI map. With the advent of JSAPI 3.4 and full AMD support this solution is showing it's age. Is this still the best/only* solution for showing Google imagery on a JSAPI map? *ESRI indicates that the WebTiledLayer will show Google imagery but does not provide an example.


title: Is it possible to use different symbols instead of colours in one shapefile in QGIS?

text: I want to show 50 bird species on a map and give each species a different symbol (with a different colour) so they can be visually distinguished in the map. Is this possible?


title: FeatureDataGrid and FeatureDataForm will not commit to database or input data

text: This is the second time that I have posted about this. In my previous question they told me I needed to enable the Feature Access capability. I did this and then it said I needed to have a Data Store with type SDE. After fighting with this for a week, I finally got the service to publish with these capabilities... and guess what... it still does not work. Below is my code and a series of screen shots. Any help is appreciated. XAML (Revelant):                <esri:Map x:Name="MyMap" Background="#FFE3E3E3" WrapAround="True"  MouseRightButtonDown="MyMap_MouseRightButtonDown" Extent="-9834972.92753924,4441899.425293319,-9833977.88119163, 4442762.485358352" Loaded="MyMap_Loaded">                     <esri:Map.Layers>                         <esri:ArcGISTiledMapServiceLayer ID="MyLayer" Url="http://services.arcgisonline.com/ArcGIS/rest/services/World_Street_Map/MapServer" />                         <esri:FeatureLayer ID="WaterValves"                                             Url="http://localhost:6080/arcgis/rest/services/CalvertCity_Test_Server/MapServer/0"                                             Renderer="{StaticResource MySimpleRenderer}"                                            OutFields="*"                                             MouseLeftButtonUp="FeatureLayer_MouseLeftButtonUp"                                             MouseLeftButtonDown="FeatureLayer_MouseLeftButtonDown_1"                                             DisableClientCaching="True"                                            OnDemandCacheSize="0"                                            Mode="OnDemand"                                            AutoSave="False"/>                         <esri:GraphicsLayer ID="CandidateGraphicsLayer">                             <esri:GraphicsLayer.MapTip>                                 <Grid>                                     <Rectangle Stroke="Gray"  RadiusX="10" RadiusY="10" Fill="#77FF0000" Margin="0,0,0,5" >                                         <Rectangle.Effect>                                             <DropShadowEffect/>                                         </Rectangle.Effect>                                     </Rectangle>                                     <Rectangle Fill="#DDFFFFFF" Stroke="DarkGray" RadiusX="5" RadiusY="5" Margin="10,10,10,15" />                                     <StackPanel Orientation="Vertical" HorizontalAlignment="Center" Margin="30,20,30,30">                                         <TextBlock Text="{Binding [Address]}" HorizontalAlignment="Left" Foreground="Black" />                                     </StackPanel>                                 </Grid>                             </esri:GraphicsLayer.MapTip>                         </esri:GraphicsLayer>                         <esri:ArcGISDynamicMapServiceLayer ID="CalvertCity" Url="http://localhost:6080/arcgis/rest/services/CalvertCity_Test_Server/MapServer" />                     </esri:Map.Layers>                                 </esri:Map>                      <GridSplitter Grid.Row="1" HorizontalAlignment="Stretch"/>                 <esri:FeatureDataGrid Grid.Row="2" x:Name="MyDataGrid"/>          <Grid HorizontalAlignment="Right" VerticalAlignment="Top" Margin="0,15,15,0" x:Name="USS_Data" Height="600" Width="298" Visibility="Hidden">                     <Rectangle Fill="{StaticResource PanelGradient}"  Stroke="Gray" RadiusX="10" RadiusY="10" Margin="0,0,0,39">                         <Rectangle.Effect>                             <DropShadowEffect />                         </Rectangle.Effect>                     </Rectangle>                     <Rectangle Fill="#DDFFFFFF" Stroke="DarkGray" RadiusX="5" RadiusY="5" Margin="10,10,10,48" Height="Auto" />                     <DockPanel HorizontalAlignment="Stretch"  Margin="30,20,30,30">                         <telerik:RadGridView Height="240" DockPanel.Dock="Top" Foreground="Black">                              </telerik:RadGridView>                          <esri:FeatureDataForm x:Name="MyFeatureDataForm" Height="240" Foreground="Black" DockPanel.Dock="Bottom"                                              IsReadOnly="False" LabelPosition="Left" />                     </DockPanel>                 </Grid>      Let me know if some necessary parts of my XAML are missing. C#(Relevant):               private void FeatureLayer_MouseLeftButtonUp(object sender, GraphicMouseButtonEventArgs e)             {                 FeatureLayer flayer = sender as FeatureLayer;                      MapPoint clickpoint = MyMap.ScreenToMap(e.GetPosition(MyMap));                      if (clickpoint != lastPoint)                 {                     MyInfoWindow.Anchor = clickpoint;                     MyInfoWindow.Content = e.Graphic.Attributes;                     MyInfoWindow.IsOpen = true;                     lastPoint = clickpoint;                 }                                FeatureLayer featureLayer = sender as FeatureLayer;                      for (int i = 0; i < featureLayer.SelectionCount; i++)                     featureLayer.SelectedGraphics.ToList()[i].UnSelect();                      e.Graphic.Select();                 MyFeatureDataForm.GraphicSource = e.Graphic;                     // FeatureDataFormBorder.Visibility = Visibility.Visible;                 USS_Data.Visibility = Visibility.Visible;                 PortalGrid.Visibility = Visibility.Hidden;                            }                  private void MyInfoWindow_MouseLeftButtonUp(object sender, MouseButtonEventArgs e)             {                 MyInfoWindow.IsOpen = false;                 //FeatureDataFormBorder.Visibility = Visibility.Hidden;                 USS_Data.Visibility = Visibility.Hidden;                 PortalGrid.Visibility = Visibility.Visible;             }                  private void MyDataGrid_Initialized(object sender, EventArgs e)             {                 MyDataGrid.GraphicsLayer = MyMap.Layers[1] as GraphicsLayer;             }                  private void MyMap_Loaded(object sender, RoutedEventArgs e)             {                 MyDataGrid.Map = MyMap;                 MyDataGrid.GraphicsLayer = MyMap.Layers[1] as ESRI.ArcGIS.Client.GraphicsLayer;                 MyFeatureDataForm.FeatureLayer = MyMap.Layers[1] as ESRI.ArcGIS.Client.FeatureLayer;             }                       private void FeatureLayer_MouseLeftButtonDown_1(object sender, GraphicMouseButtonEventArgs e)             {                 e.Graphic.Selected = !e.Graphic.Selected;                 if (e.Graphic.Selected)                     MyDataGrid.ScrollIntoView(e.Graphic, null);             }         }      Again, let me know if there is something that I need to include. Pictures! I will start with pictures of my settings in ArcGIS for Server: This shows that my service is running: ![running](http://i.stack.imgur.com/Wxdm3.png) This shows the capabilities: ![capabilities](http://i.stack.imgur.com/BWmGb.png) This shows the data store: ![data store](http://i.stack.imgur.com/V4FET.png) Now for what it looks like to the user... The legend with the database data: ![Legend](http://i.stack.imgur.com/hoA1X.png) The map showing the points and labels: ![Map_Data](http://i.stack.imgur.com/7gQLI.png) The Grid which will never let me commit or remove a selection: ![grid](http://i.stack.imgur.com/jWdf0.png) And the Dataform which does not have the save button like I have seen others have: ![featureform](http://i.stack.imgur.com/Udt1M.png) Warnings when Analyzing map before publishing: ![errors](http://i.stack.imgur.com/U9OiI.png) Any help will be greatly appreciated. I am at a point where I don't know where else to go.


title: TileMill OGR Plugin: Failed to read GeoJSON data

text: I'm trying to load the following into a TileMill layer as the file build1.geojson               {          "type": "Feature",         "geometry": {         "type": "Polygon",         "coordinates": [[             [752669,349453],[913955,-4919228],[4300965,-4865466],[4354727,-12499679],[-13010418,-12499679],[-13010418,-7123473]             ]]         },         "style":{             "fill":"red",             "stroke-width":"3",             "fill-opacity":0.6         }     }      However, I'm getting the error shown in the title. I can't see anything wrong with the syntax so what is my error? Is it tilemill itself?


title: ArcPy script causing python.exe to stop working (memory issue?)

text: I have a script written in Python that uses ArcPy to create maps of the kernel densities of thousands of datasets. Each dataset is relatively small, but there about 50,000 sets in total. When I run my script, it stops after about 10-15 minutes and gives the "python.exe has stopped working" popup. The Windows 7 event viewer tells me it is an Exception Code 0x0000005, which appears to be an access violation. The datasets the code works on are not the same each time, so it is not a specific set that is causing the problem. Watching the task manager when the script is running, I noticed that python.exe is increasing its memory usage every few seconds, which makes me believe there is a memory leak somewhere. I thought Python had garbage collection? Is there something that arcPy is doing? **EDIT** : So I tracked down the part of my code causing the problem, but I don't know HOW it is leaking. I think I am cleaning everything up. Does anyone spot something I missed?               def makeMap(asno, isKdens):     try:         mxd = arcpy.mapping.MapDocument("F:\\testFiles\\testMap.mxd")   ###Reference to basemap document         df = arcpy.mapping.ListDataFrames(mxd, "Layers")[0]     ###Get data frame reference in var         ##++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++         if isKdens:             ###Set up layer file             lyrFile = arcpy.mapping.Layer(r"F:\\testFiles\\output\\AS_"+asno+"_KDens.lyr")         ##++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++         else:             ###Set up layer file             lyrFile = arcpy.mapping.Layer(r"F:\\testFiles\\output\\AS_"+asno+".lyr")             lyrFile.visible = True         ###Add layer file         arcpy.mapping.AddLayer(df, lyrFile)              ###ref added layer         lyr = arcpy.mapping.ListLayers(mxd)[0]         lyr.visible = True              #If this is a raw map, just select points.         if isKdens==0:             arcpy.SelectLayerByAttribute_management ("pointslyr", "NEW_SELECTION", "\"asno\" = "+asno+"")         ##++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++         #If KDens map, apply symbology         else:             arcpy.ApplySymbologyFromLayer_management(lyr, templateLayer)         ##++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++              ###Zoom to selection         df.zoomToSelectedFeatures()         lyrExtent = lyr.getSelectedExtent()         df.extent = lyrExtent              ###Export to PDF!!!         ##++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++         if isKdens:             arcpy.mapping.ExportToPDF(mxd, r"F:\\testFiles\\output\\AS_"+asno+"_KDens_Map.pdf")         ##++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++         else:             arcpy.mapping.ExportToPDF(mxd, r"F:\\testFiles\\output\\AS_"+asno+"_Map.pdf")     except:         print arcpy.GetMessages()     #####DELETION     del mxd, df, lyrFile, lyrExtent, lyr     print "DELETED MXD AND DFS"      **EDIT 2** So, I also tried turning off logging, since I have heard that can cause memory leaks, too. There is still something leaking. I also tried using `Delete_management` instead of `del`, but that just messes things up. It almost seems like my code is not running sequentially. A delete after a reference still gives a "references before defined" error... Anyway, now I am trying to locate the memory leak using memory analyzer packages. Out of all of them that work with Python, I only got `objgraph` to work. I placed a `objgraph.show_growth` call before and after the function whose code is above. Here are the results: **Before**               tuple                         11959    +11959     function                       3643     +3643     dict                           1632     +1632     wrapper_descriptor             1086     +1086     cell                            927      +927     list                            635      +635     builtin_function_or_method      590      +590     property                        551      +551     method_descriptor               390      +390     weakref                         373      +373      **After**               weakref                 398       +25     wrapper_descriptor     1105       +19     tuple                 11977       +18     dict                   1644       +12     member_descriptor       172        +4     getset_descriptor       213        +3     method_descriptor       392        +2     instance                 15        +2     list                    636        +1     `_RLock                    2        +1      It doesn't look like any of my objects are leaking, though I am not quite sure what `instance` means in the second growth dump. Anyone have any insights?


title: uniquely identify feature classes & compare them for equality

text: I want to implement `EqualityComparer<T>` for feature classes so that I can stuff them into a Dictionary or HashSet. For motivation, say that I am looping over many IFeature objects which belong to different feature classes, and I want to set field values for each. FindField is inefficient to perform inside of a loop. If I have a `Dictionary<IFeatureClass, Dictionary<string, int>>` to give me the index of a given field, this operation would be much faster. So, how does one uniquely identify a feature class object? The AliasName property is not unique. The IName object should be, but I'm not sure how to compare them, or how to hash them. Is IDataset.Name unique to each feature class? If it is, it must include the full data path, right? Thanks!


title: Mapserver/PostGIS Query Error

text: I'm having some difficulty understanding the error I am getting from my mapserver/postgis program. I have the following map file:               MAP     # start of map file                  NAME "sample"             EXTENT  82299.5 5002.78 655979.76 657599.55             SIZE 800 400                  PROJECTION                     "init=epsg:27700"             END                  LAYER   # layer info                     CONNECTIONTYPE postgis                     NAME "roads                     CONNECTION "user=username                      password=**** dbname=databasename host=hostdb.com port=5432"                      DATA "the_geom from public.\"MLSOA\""                     STATUS ON                     TYPE LINE                      CLASS                             STYLE                                     COLOR 0 0 0                             END                      END             END         END     # end of map file      I then call this using the following command:               http://mysite.com/mapserv.cgi?map=/home/username/webapps/htdocs/mapfile_pg.map&layer=roads&mode=map      which gives me the following error:               msDrawMap(): Image handling error. Failed to draw layer named 'roads'.      sPostGISLayerWhichShapes(): Query error. Error (ERROR: find_srid()      - couldnt find the corresponding SRID - is the geometry registered in the      GEOMETRY_COLUMNS table? Is there an uppercase/lowercase missmatch? )      executing query: select encode(ST_AsBinary(ST_Force_2D("the_geom"),'NDR'),'hex')      as geom,"oid" from public."MLSOA" where the_geom && GeomFromText     ('POLYGON((-180.225563909774 -90,-180.225563909774      90,180.225563909774 90,180.225563909774 -90,-180.225563909774      -90))',find_srid('','public."MLSOA"','the_geom'))      I asked a question on GIS.SE earlier today about a problem I was having connecting to the DB, and @unicoletti helpfully solved my earlier problem about the database name. However I have now tried all the options that I understand could be causing this current error and have not figured out the problem. Things that I have tried:   1. Checking that the the table is registered in `GEOMETRY_COLUMNS` (it is, as I could not manually add it as it was there already).   2. Adding in a projection to the Mapserver file    3. Running `SELECT Probe_Geometry_Columns()` to update `GEOMETRY_COLUMNS`   4. Creating an index using the following command: `CREATE INDEX table_the_geom ON "MLSOA" USING GIST ( the_geom ); CLUSTER table_the_geom ON public."MLSOA";` Are there any other things that could be causing this error? I'm using PostGreSQL 8.3, PostGIS 1.5.3 and Mapserver 6.0.1. and these programs are all running on a Linux server.


title: What is an IFeatureClassName?

text: I'm currently attempting to export a selected set of data from a feature class in a database to another database as a new feature class. I understand everything perfectly right up to the `IExportOperation.ExportFeatureClass` bits. The last argument calls for an `IFeatureClassName` object. This appears (to me) to not be a path or a file name, but an object that maintains all of that data. I have been looking at some other questions that discuss or mention the method to export a feature class, but I cannot wrap my head around it properly. What is an `IFeatureClassName`, and how does one create it for a file that does not exist yet (the Geodatabase does exist)?


title: Identify features

text: I am new to arcgis.I am building a custom desktop GIS application using arcgis engine 9.3.1 .I want to make a custom identify tool and add it to toolbar control.Any example or code will be helpfull. Thankyou.


title: How to install grid_renderer on Linux?

text: I'm having a hard time installing grid_renderer on Ubuntu Maverick (10.10). I've followed these instructions but when I compile the mapnik branch I always get this error (http://pastebin.com/Txc5Wt9W):               [...]     scons: *** [bindings/python/mapnik_python.os] Error 1     scons: building terminated because of errors.


title: Row-crop field boundaries

text: I'm on the hunt for field boundary coordinates in the US in the form of GeoJSON, a Shapefile or any structured format that I can use to overlay on a map. I've tried looking at the US Department of Agriculture but can't seem to find it. Not sure I'm using the correct terminology for find such data.


title: Using QGIS to access data delivered by ArcGIS for Server?

text: Can I use QGIS to access data delivered using ArcGIS Server? The following servers don't seem to be compatible with QGIS http://www.topofthesouthmaps.co.nz http://gis.wcrc.govt.nz/arcgis/rest/services


title: GDF -- Can anyone suggest some good reading?

text: Can anyone give me a nutshell explanation of the Geographic Data Files format, or post a few URLs I might find enlightening? I get the sense (although I'm not sure) that GDF implies building certain topological relationships, frictions, rules, etc into the spatial database. I don't quite get certain facets of what I've been reading so far though. It looks as though the format is mostly relevant to routing-typed applications like pipelines, hydro networks, fleet navigation routing, etc. Is this not something best done with an extension like Network Analyst, or is this something that's done with scripting or programming languages. Why the "stand alone" environment outside of GIS applications. I can't find anything that's leading to the answers I'm after. Can anyone give me the "for dummies" version? Why would there be any reason to do this "outside" of a GIS environment. From what I've read, it looks as though the final product is delivered in some sort of "textual" framework.


title: Converting table drawn as annotation in AutoCAD to format suitable to link attributes to cables in ArcGIS for Desktop?

text: I am working on cables and each cable has attributes. I want to link these attributes to the cables in ArcGIS for Desktop. When I open these cables in AutoCAD it appears that their attributes are drawn as annotation. I would like these attributes to be in a table. Later I need to export the data to an Excel spreadsheet. There is an example of the Table open in AutoCAD below. ![enter image description here](http://i.stack.imgur.com/9YLRt.png)


title: How do I import a PNG as a TileMill layer?

text: I want to use the NASA "Blue Marble" images as the basis of a map tile set for a Leaflet.js map. It seems like using TileMill is the easiest way of building up my tiles, and opens a lot of options down the road. However, it doesn't appear that I can import a plain "PNG" file as a layer. PNG files don't normally apper as a file data source, and when I force it, I get the following error:               ---------------------------     TileMill Error     ---------------------------     [tilemill] [tilemill] problem loading datasource     Error: Unable to determine SRS for layer  "world" at C:\Users\jklemmack\Desktop\world.200412.3x21600x10800.png     [tilemill]     at Function.resolved.srs (C:\Program Files (x86)\TileMill-v0.10.1\tilemill\node_modules\millstone\lib\millstone.js:785:37)     [tilemill]     at next (C:\Program Files (x86)\TileMill-v0.10.1\tilemill\node_modules\step\lib\step.js:51:23)     [tilemill]     at Function.resolved.Layer.forEach.name (C:\Program Files (x86)\TileMill-v0.10.1\tilemill\node_modules\millstone\lib\millstone.js:716:29)     [tilemill]     at next (C:\Program Files (x86)\TileMill-v0.10.1\tilemill\node_modules\step\lib\step.js:51:23)     [tilemill]     at Step (C:\Program Files (x86)\TileMill-v0.10.1\tilemill\node_modules\step\lib\step.js:122:3)     [tilemill]     at resolved.srs (C:\Program Files (x86)\TileMill-v0.10.1\tilemill\node_modules\millstone\lib\millstone.js:712:21)     [tilemill]     at Object.fs.exists [as oncomplete] (fs.js:91:19)          Please report this to https://github.com/mapbox/tilemill/issues      I attempt to specify the SRS as WGS84 (per NASA's readme) and I get:               Could not create datasource. No plugin found for type 'undefined' (searched in: C:\Program Files (x86)\TileMill-v0.10.1\tilemill\node_modules\mapnik\lib\mapnik\lib\mapnik\input)      Any help? Is this even possible? Do I have to slice up the PNG with some other tool?


title: Python script (ArcPy) crashing one machine, but works on others?

text: I have been woking on a script that will select parcels that are within a particular ArcGIS 10.1 data driven page, create a list out of those parcels, and then populate a text element within my MXD with the parcel list. I run this script from CMD right after I restart the machine, and it works fine. But as soon as I try to rerun it(without reboot), the script errors out. I get no error message at all other than the generic Python.exe has stopped working. I work on a workstation with Windows 7 Pro, 3.4GHz processor with 8GB RAM, ArcDesktop 10.1, and python 2.7. What might be the possible reasons for python to fail? Are there issues within my script? Any help would be greatly appreciated. The print statements are in the script as I was trying to trouble shoot where it was crashing.               import sys     import arcinfo     import arcpy     sys.path.append("R:\ARCGIS_SCRIPTS\General")     import DatabaseFunctions     arcpy.ClearWorkspaceCache_management()          def main(args=None):         #if args is None:             #args = sys.argv[1:]         #UserInput = (args[0])         UserInput = arcpy.GetParameterAsText(0)               try:         try:             arcpy.AddMessage('1')             arcpy.CheckInExtension("Foundation")             arcpy.AddMessage('1')         except Exception as e:             print e         try:             arcpy.AddMessage('1')             arcpy.CheckInExtension("Datareviewer")             arcpy.AddMessage('1')         except Exception as e:             print e              ## Input from user         PageNameList = [UserInput] #["1N1E03"]         #OutputFolder = "C:\\Dan\\PythonWrestling"         OutputFolder = "C:\\Joey"              ## Hard coded resources         MapFolder = "C:\\Joey"         #MapFolder = "C:\\Dan\\PythonWrestling"         vector = DatabaseFunctions.CreateDatabaseConnection(Database="Vector")         mxd = arcpy.mapping.MapDocument(MapFolder + "\\SectionMap.mxd")         arcpy.AddMessage(mxd)         layerlist = None         del layerlist         layerlist = arcpy.mapping.ListLayers(mxd)         arcpy.AddMessage(layerlist)         for lyr in layerlist:             if lyr.name == "Parcels":                 PLyr = lyr             if lyr.name == "Page":                 PGLyr = lyr         #PLyr = arcpy.mapping.ListLayers(mxd, "Parcels")[0]         #arcpy.AddMessage('1')         #PGLyr = arcpy.mapping.ListLayers(mxd, "Page")[0]              ddp = mxd.dataDrivenPages         for pageName in PageNameList:             ddp.currentPageID = ddp.getPageIDFromName(pageName)                  ## Create parcel list             arcpy.MakeFeatureLayer_management(vector + "\\vector.DBO.parcels", "thingy")             arcpy.SelectLayerByLocation_management ("thingy", "HAVE_THEIR_CENTER_IN" , PGLyr)             sCursor = arcpy.SearchCursor("thingy",fields="PARCEL")             parcelSetUnsorted = set()             for row in sCursor:                 eachParcel = row.PARCEL                 if isinstance(eachParcel,basestring):                     parcelSetUnsorted.add(eachParcel)             parcelSet = sorted(parcelSetUnsorted)             parcelListStringList = list()             parcelListText = ""             count = 0             print str(len(parcelSet)) + " parcels in the set."             for eachParcel in parcelSet:                 count = count + 1                 parcelListText = parcelListText + eachParcel + "\n"                 if count == 70:                     if (len(parcelListStringList) == 5):                         parcelListText = parcelListText + "And more..."                         parcelListStringList.append(parcelListText[:])                         parcelListText = ""                         continue                     parcelListStringList.append(parcelListText[:])                     count = 0                     parcelListText = ""             if len(parcelListText) > 0:                 parcelListStringList.append(parcelListText[:])                  arcpy.AddMessage(parcelListStringList)                  ## Put correct text in each text element             elmList = arcpy.mapping.ListLayoutElements(mxd, "TEXT_ELEMENT")             upperx = .5             uppery = 10.0             ydelta = .75             xdelta = .9             ylower = .75                  for elm in elmList:                 if elm.name == "ParcelList":                     elementCount = 0                     elm.elementPositionX = -5                     for parList in parcelListStringList:                         eachElm = elm.clone("_clone" + str(elementCount))                         eachElm.elementPositionX = upperx + (elementCount * xdelta)                         elementCount = elementCount + 1                         print "--- " + parList                         eachElm.text = parList                 #elif elm.name == "MapTitle":                     # elm.text = titleText             ## Export as a PDF             arcpy.AddMessage('Exporting Page')             mxd.saveACopy(OutputFolder + "\\" + str(pageName) + ".mxd")             #arcpy.mapping.ExportToPDF(mxd, OutputFolder + "\\" + str(pageName) + ".pdf")     except Exception as e:         print e     del mxd                    if __name__ == "__main__":         sys.exit(main())


title: Prevent self-intersecting loops when exporting polygon layer from ArcSDE to File Geodatabase?

text: I am using ArcGIS 10.1. The source data is housed in an ArcSDE instance that does not allow self- intersections. When I export this data to a file geodatabase and run check geometry self- intersections come up. Then I run repair geometry and the tool runs fine and says it fixed self- intersections. I need all the features to be one large feature for my union step, so the next thing I do is select all the features and merge them together in an editing session. After the merge there is again bad geometry. Why is bad geometry being introduced and is there any way to prevent it?


title: Compatibility between ArcGIS for Desktop 10.2.1 and Node4j databases

text: The software that I use for spatial analysis and database connection with an external database is ArcGIS for Desktop 10.2.1, by Esri. Do you know if it is technically possible to connect ArcGIS for Desktop to a Node4j database? And how to do that?