Differences in raster extents in gdalinfo, SAGA & Quantum after resampling

I recently resampled a raster file using SAGA's Resampling module. The aim was to widen the extent of the new raster to two decimal places, where the original raster has three decimal places. The resolution of the raster stays the same with 0.02. I take the extent of the original raster and calculate the extent of the additionally needed input-raster from it. For example - Orginal raster upper left corner:   * This is what gdalinfo tells me:              589262.561, 5955004.195        * What I see with SAGA hard zoom to displayed raster:              589262.561, 5955004.195        * What I see in SAGA-Metadata instead:              589262.571, 5955004.185        * What I see with Quantum hard zoom to displayed raster:              589262.561, 5955004.195        * What I see in Quantum Metadata:              589262.5609, 5955004.1949      The given numbers of lines and columns are all the same from gdalinfo to SAGA and Quantum. Why is there such a difference in displaying the raster in SAGA? After resampling with the calculated input grid I get the following:               gdalinfo:         589262.550, 5955004.210     SAGA-zoom:        589262.570., 5955004.190     SAGA-metadata:    589262.56, 5955004.2     Quantum-zoom:     589262.570., 5955004.190     Quantum-metadata: 589262.550, ,5955004.209      Again such differences between displaying the raster and its actual metadata. However, the amounts of lines and columns are identical again, though the other corners also differ slightly. Is there generally such inaccuracy in these programs? Is it somehow caused by the resampling module? Which information should I believe for further use of the raster? A lot of information and questions--I would be grateful to get an answer anyway.


Which CRS would you use to georeference historical world maps?

Which CRS would you recommend to georeference historical world maps like the ones in the London Geographical Institute - The Peoples Atlas - 1920, e.g. ![enter image description here](http://i.stack.imgur.com/dUT1n.jpg) The map displays a lat/lon grid which I would like to use to pick control points. I managed to get some reasonable results simply using WGS84 EPSG:4326 but wonder if there isn't a better option.


Why won't QGIS recognize my GPS?

Garmin BaseCamp recognizes and receives data from my GPSmap 60CSx, but QGIS GPS Tools plugin does not. Am I missing a step? I want to be able to transfer data both directions. MacOS 10.6.8 QGIS 1.7.2


Send ArcGIS JavaScript Geometry Object JSON to server using JQuery Ajax request

I need to send ArcGIS JavaScript Geometry Object JSON string to Asp.Net Handler. I am using JQuery Ajax request to post the Geometry Data. I am not able to pass JSON geometry like this JSON.stringify(geometry.toJson()). Here is my code.               var jsondata = JSON.stringify(geometry.toJson());          $('#ajax-button').click(function () {        $('#frmUpload').ajaxSubmit({          data: jsondata,         contentType: "application/json; charset=utf-8",         dataType: 'json',         success: function (r) {            $('#ajax-results').html(r);           $('input:file').MultiFile('reset'); < br >         }       });     });


r.mapcalculator and python again

I've been trying to write a script creating binary maps:               a=raw_input ("enter a threshold")      b=float(a)      grass.run_command('r.mapcalculator', formula="**'base_map'>=b**", outfile='map'+str(a), overwrite=True)       When I'm trying to execute it there's an error message :               Invalid map     Parse error       Obviously, when the relevant part of the code is changed (e.g. `formula="'base_map'>=**0.7**"`) everything is working fine. However, my goal was to write a script creating a map automatically when the "a" (the threshold) is provided. I would be grateful for any hints. Cheers


ArcObjects: How to measure the draw time of a layer in ArcMap?

I'd like to quantitatively measure the display performance of mosaic datasets, image service layers, raster layers, feature layers, etc. in ArcMap 10. How can I measure the draw time of a particular layer (or the complete drawing process if that is the only option) in ArcMap? What are the interfaces, objects and events involved? Is the StopWatch class in .NET suitable for accurately measuring this type of operation? Has anyone already created an ArcMap add-in or extension for this purpose?


Generate Near Table and keep all attributes

I am trying to calculate the angle and distance of points to surrounding polygons. The table is good and what I need but it doesn't maintain all records; the unique point and polygon IDs are not there. Is there a way to maintain those? I will need them for further calculations. I'm using the "Generate Near Table" tool in ArcGIS 10. There are complete columns missing. I have a specific ID number assigned to each record and that column amongst others that I don't care about as much, didn't come with. The rows seem all there, I think, but not all columns. I can't join the near table with any data layer either to get that column back.


ArcGIS reloadData runs very slow on iOS

So I have some points on a map. I've written code to allow the user to drag a point around the screen which more or less looks like this.               - (void) mapView:(AGSMapView *) mapView didMoveTapAndHoldAtPoint:(CGPoint)screen mapPoint:(AGSPoint *)mappoint graphics:(NSDictionary *) graphics    {         [self.polyLine updatePoint:mappoint onPath:0 atIndex:self.indexOfPointBeingMoved];         [layerThatThePolyLineIsIn dataChanged];     }      However, this implementation seems to be amazingly laggy. Is it just me or the esri's ArcGIS SDK very bogged down and inefficient?


How do I search dates using the ArcGIS REST API?

I'm trying to understand how dates are queried in the ArcGIS Server REST API (v10) using the query functionality (`...MapServer/find?searchText=...`). If I search on a string attribute I can get a result and its date field shows the value "6/1/1995". However if I then search by the date field using "6/1/1995" I get 0 results. Am I supposed to provide my date in a particular format? I tried reversing the date's components' ordering, changing the separator, with/without leading zeros, and even tried the timestamp to no avail. I'm not in control of the service or the data so I don't know if any settings are in place in the source data that make this more difficult. The field's format is reported as `esriFieldTypeDate` with length 36. This thread suggests I should be seeing the date field reported as a timestamp in the JSON output of my query but in both HTML and JSON it is "6/1/1995". I saw this thread on the ArcGIS forum but as using a timestamp didn't help me I assume it's not relevant. Any hints much appreciated.


ArcObjects - Possible To Add Anything More Than Text To Balloon Callout?

With code I've scraped together from various posts on this site, I am able to display a simple balloon callout with text in a standard ArcMap session. Is it possible to add anything more than just text, for example some html or even something like a windows form? I am aware of HTML popups - but I don't think they will work for my situation. Without getting to verbose here, the point locations and associated content I want to display don't reside in any feature class. Instead, I have an event handler wired up in ArcMap listening to an external source that invokes the handler with point location & content. Any thoughts or suggestions?               IMxDocument mxDoc = (IMxDocument)m_application.Document;     IActiveView activeView = mxDoc.ActiveView as IActiveView;     ITextElement pTextElement;     IElement pElement;     ICallout pCallout;     IFormattedTextSymbol pTextSymbol;     IGraphicsContainer pGraphicsContainer;          IPoint anchorPoint = new Point();     anchorPoint.PutCoords(0, 0);          pTextElement = new TextElementClass();     pElement = pTextElement as IElement;     pTextElement.Text = "HELLO WORLD!!!!!!!!!!!!!!!!";          ESRI.ArcGIS.Display.IScreenDisplay screenDisplay = activeView.ScreenDisplay;     ESRI.ArcGIS.Display.IDisplayTransformation displayTransformation = screenDisplay.DisplayTransformation;          int x, y;     displayTransformation.FromMapPoint(anchorPoint, out x, out y);     IPoint messagePoint = displayTransformation.ToMapPoint(x, y - 100);     pElement.Geometry = messagePoint;          pTextSymbol = new ESRI.ArcGIS.Display.TextSymbol();     pCallout = new BalloonCallout();     pTextSymbol.Background = pCallout as ITextBackground;     pCallout.AnchorPoint = anchorPoint;     pTextElement.Symbol = pTextSymbol;          pGraphicsContainer = activeView as IGraphicsContainer;     pGraphicsContainer.AddElement(pElement, 0);     pElement.Activate(activeView.ScreenDisplay);     activeView.PartialRefresh(esriViewDrawPhase.esriViewGraphics, pElement, null);


Turning off 'hover' feature in CartoDB

**_UPDATE: See comment below - this was a bug that was fixed unbeknownst to this thread... thank you all!_** Is it possible to turn off the 'hover' feature in CartoDB? I have toggled off all the fields from the 'hover' menu, which in the visualization wizard shows as being 'off', but when I visit the embedded map on the webpage consuming it, the hover is still on, and 'no data available' shows in the hover window. Thanks!


WFS 2.0 with bbox filter and attribute filter

I am trying to get the following WFS GET request to work:               wfs = "service=WFS&version=2.0.0&request=GetFeature",     name = "&typeName=storeName:layerName",     bboxFilter = '&bbox=' +  bounds._southWest.lng + ',' + bounds._southWest.lat + ',' + bounds._northEast.lng + ',' + bounds._northEast.lat,     attributeFilter = '&name=test',     format = "&outputFormat=text/javascript&format_options:callback:getJson",     urlWFS = "http://domain.com:8080/geoserver/bla/ows?" + wfs + name + bboxFilter + attributeFilter +  format;      It works fine with the bounding box filter, but the attribute filter is simply ignored. What is the right syntax for that?


How to provide automatic overview map, ArcGIS 10

This is a slightly badly phrased question I know, but I'm not really sure what to call this. My supervisor recently showed me a printed out map that he had produced with a high-resolution satellite image on one side, and then an overview map of the whole of the UK on the other side, with a dot marking the location of the satellite image. He said that this was produced automatically using ArcGIs, and he didn't have to manually add a point to the overview map with the right co-ordinates. Unfortunately he has been unable to find time to help me with this, and I have been looking for how to do this, but as I don't know the name of this process it is very difficult to find it. Does anyone have any ideas what this process/technique is called, and how I should go about doing it?


Cursor Update Python Script for Multiplying Several Fields against a Ratio (Real) in ArcGis

![enter image description here](http://i.stack.imgur.com/VjbrM.jpg)Disclaimer: Python Neophyte, Uber-reliant on GUI, working to wean... I have a Python script for replacing multiple Field values with another table value that was graciously provided by the inimitable DKlassen and seen here:               import arcpy     tablename = "c:\temp\*NAMEOFYOURTABLE*"     fieldvalues = ['fieldname1','fieldname2','fieldname3'......'fieldnameX']          cur = arcpy.UpdateCursor(tablename)     for row in cur:         sourcevalue = row.getValue('*name of field where source value coming from*')         for f in fieldvalues:             row.setValue(f, sourcevalue)         cur.updateRow(row)      Question: After running it it seems to replace all the fieldvalues with f and defaults integers to 0 or 1 (since sourcevalues is a real number between 0-1)--how do I include an operator to multiple for f in fieldvalues by a ratio, or real/float number? Obviously the syntax of f*sourcevalue does not work.


Getting coordinates to create geojson

I have a geotiff that I have been working with in tilemill and I would like to select portions (buildings) in the map and create new layers as geojson objects. My issue is I don't know how to get the coordinates to create the objects! http://chimera.labs.oreilly.com/books/1230000000345/ch12.html#_choropleth this is a link to what I'm trying to do with states I just need the step where the coordinates are gotten because it doesn't seem to be in this document, they just give a shout to the guy who defined them. If anyone has done something similar to this, please give me a shout! TO CLARIFY I am not looking for the coordinates for the 50 states, I am trying to create geojson objects for a FICTIONAL map.


The Best books from ESRI

Which books from ESRI Press can you recommend? Anticipate your suggestion that i should give a specific topic I just want to know what can you recommend as you like the most (can be any topic- because ESRI Press has the most books related to GIS topic).


How to permanently join MDB database (access) table with spatial data in ArcGIS for Desktop?

I have an Access file (*.mdb), and I want to join between this attribute data with its spatial data ? But other than (join & relate way) . And I need it to be permanent .


Action: open file from database

I have an image stored in a db (postgres / bytea). Is it possible to display (open) this image with a qgis action?   In Qgis I have a (postgis) layer open, one attribute is the id of the image in the image-table in the database. The image-table has no geometry, just the images as bytea. Any help would be appreciated. thanks


ArcPy x64 - Create Enterprise Geodatabase in SQL Server Fails

I'm using ArcGIS Desktop Standard 10.1 SP1 on Windows 7 SP1 x64. SQL Server Native Client 11.0 is installed for both 32 bit and 64 bit. I've also got SQL Server 2012 x64 installed (client tools and database engine). Running an ArcPy based script in Python 2.7 x64 crashes Python.exe when it tries to create an Enterprise Geodatabase in SQL Server 2012 with this line:               arcpy.CreateEnterpriseGeodatabase_management("SQLSERVER", sDbServerName, sDbName, "OPERATING_SYSTEM_AUTH", "", "", "DBO_SCHEMA", "", "", "", sLicenseKey)       The error is: > Unable to load server library (c:\program files > (x86)\arcgis\desktop10.1\bin\sdesqlsrvr101.dll), Error = -324 Using SDE_SCHEMA and/or database authentication don't work either. The workaround is to use 32 bit Python. However, our standard development environment is x64 (for performance reasons). Any ideas how to get this working in x64 Python?


Is GeoServer getting coordinate output in GeoJSON WFS wrong?

When I do a WFS request to GeoServer and specify the SRS like this:               http://myserver.com/geoserver/wfs?         service=wfs&         version=2.0.0&         request=GetFeature&         outputFormat=application/json&         srsName=EPSG:4326&         typeName=MYWORKSPACE:mylayer      I get exactly what I expect and it works fine. When I remove the `srsName=EPSG:4326` parmeter I get GeoJSON that still identifies itself with:               "crs": {         "type": "EPSG",         "properties": {             "code": "4326"         }     }      but the order of the coordinates is reversed, so it doesn't work. Are both of these valid EPSG:4326 output, or is one of them wrong? The layer I'm working with has these settings:   * **Native SRS:** EPSG:4283   * **Declared SRS:** EPSG:4326   * **SRS handling:** Reproject native to declared


Is there a Free Opensource Shapefile Writer for .NET?

I am looking for a well documented, OpenSource Library that can create and write to a shapefile from .Net. I need lower lever access:i.e. I should be able to write feature by feature. Does such a library exist? I have investigated and found the following:   * SharpMap claims to write to shapefiles in v 2.0, but that version has not released.   * NTS has absolutely no documentation.    * Catfood shapefile reader provides read only access. Is there any hope for me? Is there a library that can be used to write a new shapefile?


What's the ArcObjects equivalent to ArcMap's Flip button

In an ArcMap extension, I need to flip multiple lines from a selection. The ArcMap Flip button only allow to flip one feature at a time. What's the ArcObjects equibalent to the ArcMap's flip button? ![enter image description here](http://i.stack.imgur.com/cyKoG.jpg)


Order of rings in ESRI Sliverlight API query task

I have an problem with "Query Task" class of ESRI Sliverlight API 2.1 version. I am saving a polygon with 2 exclusions [Inner rings] (i.e. say exlcusion 'A' as 4 vertices and exclusion 'B' with 5 vertices) into SDE database.When I do a Sliverlight ESRI query task to retrive the same shape, am getting exclusion B as first inner ring and exclusion A as second inner ring.How do I get a polygon rings (inner) in same order as I saved into database. I have tried Simplify method but still no luck. Note: shapes from sliverlight has been saved to SDE using GP Tools where inner rings are added into geometry bag in same order and stored in geodatabase. Let me know if any questions. Posted in ESRI forums no help as on today hence posting here. * * * Hi Petr and Krik: Thanks for your answers. From Silverlight client am sending polygon as feature set to store in SDE using GP Tool. In the ArcObjects part of the code, we create the rings and add them to a `IGeometry` array. The outermost ring gets added first, followed by the inner rings(in the same order in which they were created). Finally `IGeometryBridge.AddGeometries` method was used to build a polygon from array of rings. When we check the interior ring order after creation of the polygon geometry, it reflects the same order in which it was created in the Silverlight API. But once we store it in a SDE geodatabase featureclass, immediately the interior ring order gets modified. I have asked same question in ESRI Forum. ESRI expert saying that order of rings will be changed for performance reasons while storing in SDE. Because of this when I query the same polygon using query task of Silverlight API, order of rings are changed. If you look into Arcobjects, I can get order in same way using               SimplifyPreserveFromTo((ITopologicalOperator4)inputPoly).IsKnownSimple_2 = false;     inputPoly.SimplifyPreserveFromTo();      What is equivalent of `SimplifyPreserveFromTo` in ESRI Silverlight, or any best approach to get rings in same order. Here important point - rings are not changed always, some times I am getting correct order while retriving from query task of Silverlight API. Please help me on this further. Thanks in advance.


NoData in ArcGIS Spatial Analysis

When using Spatial Analyst I regularly have issues with NoData values cropping up in the data. Various tools appear to introduce NoData values regularly. These values then cause issues with other tools and have to be eliminated with reclassification, usually resulting in other problems. How should NoData values be dealt with? Is there a simple way to replace NoData values with zero? Can NoData be avoided altogether?


Polygonize a raster using GDAL JAVA bindings - passing raster pixel value to the resulting feature

I have a raster GeoTIFF file with values from 0 to let's say 5. When I run gdal.polygonize (I'm working with JAVA and GDAL bindings to JAVA) on it, I get features with corresponding polygons. The problem is that the value of the raster pixels are not passed anywhere and I lose the information about which polygon belongs to which value. Is there any way to store this information anywhere? PS. Sorry if the question is not clear. This is my first experience with GIS world (and with advanced programming also to be honest :) )


Pick Address From Map tool won't work

I tried to ask this question before and I made a mess of it. I have edited the question to what I hope will be a more understandable form. Please help me if you can! We just installed Service Pack 5 to our ArcMap 10 software. This allowed us to build a composite address locator based on the new streetfile and address pointfile built by our area 911 authority. The new locator works very well, but when I am manually rematching a recently geocoded file and try to use the "Pick Address From Map" tool, the record shows as matched in the table, the XY data is added, but there is no point on the map. I geocoded the same data set with both our old and the new locator, then tried using the "Pick Address From Map" tool on each of the resulting shapefiles. I attempted to place the same unmatched record in each instance. If I use our old locator to do the original geocoding the tool works just fine, which indicates that this is a locator-specific problem. Again, in the shapefile resulting from our old locator the tool worked perfectly; in the shapefile resulting from the new locator the tool didn't work at all. I can't figure out why. Does anyone have any suggestions as to why the tool would not work, or any idea how to repair it? I appreciate any help. Thanks, George


How do I get a count of all the dead end streets?

I'm working in ArcGis 10.1 - Advanced and I wanted to know how can I identify and get a count of the number of dead end streets in my road network?


Can we use GeoExt Freely?

I want to know, can we use GeoExt freely? is there any need to purchase some license for using GeoExt ? Actually i am already working with free Open source tools (OpenLayers+GeoServer) for my webMap applications. But i need some specific functionality which is possible with GeoExt. so can i use GeoExt freely with Openlayers and GeoServer ?


Using annotation layer inside group layer without getting error adding element?

How do you get an annotation layer working inside a group layer? When I try, I get the error message "error adding element". I have a project that requires several annotation layer to be organised within a Group Layer. Tested in ArcMap 9.3.1 and 10. Steps to reproduce:   1. Create a new document   2. Add a Annotation Featureclass to ArcMap   3. Start Editing   4. On the Draw Toolbar, change the Active Annotation Target to the Annotation Featureclass   5. Draw something (e.g. freehand) - This should work!   6. Create a New Group Layer   7. Move the Annotation Featureclass inside it.   8. The Annotation Target has now been lost!   9. On the Draw Toolbar, change the Active Annotation Target to the Annotation Featureclass   10. Draw something (e.g. freehand) - This does not work!   11. You will get the error message "error adding element" You will now not be able to write to this Featureclass unless you save the document, close ArcMap and re-open it. This is not an acceptable workaround for my project. Is there a workaround, preferably in ArcObjects? This might relate to an **ArcMap 8.3 bug submitted in 2001**.


Create 10.0 compatible Mosaic Dataset with 10.2 (or something else)

I have a client who requested a ArcGIS mosaic dataset, but as I found out today they only have licenses for ArcGIS 10.0, and I only have licenses for 10.1 and 10.2. The mosaic datasets I create cannot be viewed on their systems. Is there any way to create a backwards compatible mosaic dataset with what I have? If not, are there any tools available elsewhere that would accomplish this (aside from getting a license for 10.0)?


which mobile gis application developing is better for me

I want to develop a mobile app with the following features:   1. work offline on mobile and don't need access to the internet (disconnect mode)   2. can import layers to it in public extensions (shape file, personal geodatabase, kml)   3. can edit layers   4. have some forms and fields that get filled out by mobile user and save in database I think Android is a better platform for developing my app, so I need a GIS service that can extend in Android. I know ArcGIS and developed web apps and desktop apps with that before, but in mobile app developing, I can't use it, because I had to use the ArcGISOnline service to host my layers and I don't want share my map and want to host data locally and offline. I'd like to know:   * what I need   * what GIS service should us   * what platform I should choose   * which is better


Viewsheds and Observer Points in ArcGIS Spatial analyst

I am trying to understand the viewshed and observer points tool in spatial analyst. I want to show which areas of land can see a wind turbine, or put another way, from where can the wind turbine be seen! In my simplified model I have just the DEM and a point shp which contains the following fields: OFFSETA and OFFSETB. I have read the ESRI Documention and OFFSETA is the height of the observer over the DEM and OFFSETB is a height of an object over the DEM. If I calculate the viewshed as follows: OFFSETA= 1.65 (Eye-level) and OFFSETB = 50 (the top of the windturbine) what am I actually calculating? Could it be all cells which the observer (at a height of 1.65m above the DEM) would observe if a 50m tall wind turbine would stand in every cell???? in other words... these are the cells in which a 50m tall wind turbine could be seen from the observation point? OR Because I want to know from where the turbine is visible, I thought I should put the observer´s eye-level on top of the wind turbine (50m). Now I can just calculate all cells that I can observe on the DEM + 1.65. If I can see then from the top of the turbine then I am assuming they can see me, right? Now the practise: I created two viewsheds as above described. Image 1: OFFSETA= 1.65 & OFFSETB=50 ![OFFSETA= 1.65 & OFFSETB=50](http://i.stack.imgur.com/MDm9i.png) Image 2: OFFSETA50 & OFFSETB= 1.65 ![OFFSETA50 & OFFSETB= 1.65](http://i.stack.imgur.com/2giRV.png) The two approaches gave two very different pictures When the OFFSETA = 50m I get these straight lines. I am trying to understand why. If anyone can help, I would be most pleased, thanks in advance, Robert


How to unload() a plugin in QGIS 1.7?

I am writing a python plugin for QGIS 1.7 (started it on QGIS 1.6 but switched to 1.7 recently). Since I switched to 1.7 my unload function doesn't seem to be working anymore. Whenever I implemented changes to the code I use the "Plugin Reloader" plugin to load the newest version of my code. In the MenuBar this causes an additional, new instanec of the plugin to load while it doesn't unload the old ones. After doing this a couple of time I end up having a list of endless outdated outdated references to my plugin. For the menu bar icon the same does NOT happen... The code worked fine in 1.6 and I seem to be correctly following all the online examples. It shouldn't be a problem, that I'm creating two actions, at least the PluginReloader plugin seems to do the same.               def initGui(self):          [...]         # GemEB Tool         self.action_tool = QAction(QIcon(iconpath), u"GemEBTool", self.iface.mainWindow())         self.action_tool.setWhatsThis(u"GemEBTool")         self.iface.addPluginToMenu("&GemeindeEnergieBeratung 1.5", self.action_tool)         self.iface.addToolBarIcon(self.action_tool)         QObject.connect(self.action_tool, SIGNAL("triggered()"), self.run_tool)              # Solarrechner         self.action_solarrechner = QAction(QIcon(iconpath), u"GemEB Solarrechner", self.iface.mainWindow())         self.action_solarrechner.setWhatsThis(u"GemEB Solarrechner")         self.iface.addToolBarIcon(self.action_solarrechner)         self.iface.addPluginToMenu("&GemeindeEnergieBeratung 1.5", self.action_solarrechner)         QObject.connect(self.action_solarrechner, SIGNAL("triggered()"), self.run_solarrechner)          def unload(self):         # GemEB Tool         self.iface.removePluginMenu("&GemEBTool",self.action_tool)                 self.iface.removeToolBarIcon(self.action_tool)              # Solarrechner         self.iface.removePluginMenu("&GemEB Solarrechner",self.action_solarrechner)                 self.iface.removeToolBarIcon(self.action_solarrechner)


Calculate the distance between two contours

I have two contour polylines (single shapefile) and I would like to calculate the mean, min and max distances between the two lines. Is there a function in ArcMap 10 (ArcInfo license, incl. Spatial Analyst) that will do this for me without have to use the measurement tool manually? The measurement should account for the curvature of the earth.


Controlling Python Version from ArcGIS?

I am writing a VB.net console application that calls ArcGIS Desktop 10.1 ArcToolbox geoprocessing tools from my code. Some of these tools use Python syntax and I am encountering a problem that I suspect is caused by conflicting architectures. Is there a way to control which version of Python that ArcGIS uses?   * System: 64 bit Windows 8.1   * ArcGIS: 32 bit ArcGIS 10.1 Service Pack 1   * Python: Both 32 and 64 bit versions installed (latter from ESRI's background processing download)   * My App: 32 bit VB.net (not Any CPU) console application.


How to access QGIS Plugin Repositories from behind a proxy?

I have been trying to teach myself QGIS by using this forum and others to help. Most of my questions can be answered by downloading plugins that are available through 3rd party repositories but for some reason I am not able to connect with these. Anyone have any ideas why this is the case?


Select top 5 most items in a geodatabase

I'd like to know what is the best way to select the 5 most expensive items (in terms of actual monetary value) in my geodatabase where i have a price field. Prices are not necessarily ordered but can be. I'm looking for an elegant SQL solution for this, but currently it seems TOP and LIMIT are not supported in ArcGIS 10 and there is no specific tool to limit your search to just 5. My solution would be to use the IN and TOP 5 keywords like so "SELECT * FROM myTable WHERE itemPrice IN (SELECT TOP 5 "itemPrice" FROM myTable)" I get an error about the SQL syntax, but when i hardcode the values for the top 5 most expensive the query works i.e. "SELECT * FROM myTable WHERE itemPrice IN (100, 105, 110, 125, 150)" I am trying to use the query builder to create a model in ArcMap that will select only the five most expensive items in the attribute table of a feature class. Thanks


Create Georeferenced Raster For JPEG file with Mapnik Python

I am able to use Mapnik generate_image.py to generate image with a BBOX and projection. Also, I have added a python script to generate a JGW file. But to completely georeference the generated image. I guess I need to add projection information to it. I found out it can be done via .prj file. But not sure if it can be generated via python script. Is there any way to do the same? Is only generating .jgw file the way to completely georeference the image? Thanks a lot in anticipation.


How to update a Vector layer with WFS protocol, after updating the filter?

I am using a Vector Layer with WFS protocol to show only a subset of the data. The filter which defines the subset, changes dynamically from the code. How do I refresh the layer, to show only the data that satisfies the new filter? layer.refresh(); does not work.


Geoserver does not show sql data store

I've just installed Geoserver 2.3-RC1 on windows 7 64bit and JRE 6.43 and downloaded the relevant sql extensions and Microsoft files . As instructed , I've copied "gt-jdbc-sqlserver-9.0-RC1.jar" to "C:\Program Files (x86)\GeoServer 2.3-RC1\lib" and also the x86 versions of "sqljdbc_auth.dll" and "sqljdbc_xa.dll" to "C:\Windows\System32". I've restarted geoserver and went to Add Store and still didn't see SQL option. I've tried doing the same with the x64 versions of the dlls , same result. What am I missing ?!


calculating bounding box from known centre coordinate and zoom

I have a map, the centre of that map (centrepoint) is = -37,175 ( gps)   I know the zoom of the map = 13   I know the size = 320x320px   I know there is 111111m in a degree of latitude and a varying degree in longitude I want to be able to calculate the value to add and subtract from the centre coordinate that will give me an upperleft/lowerright gps coordinate. For a zoom of 13 I used to achieve this by Note :centrelat= -37   eg :-37 - (-37/1650) = -36.9776 deg. In other words to find the southeast corner we subtracted .0228 degrees from the centre coordinate. I did the same for longitude but used the value 6250   eg :175 - (175/6250) (.02804 degrees). = 174.792, ie the northwest corner   the ratio between .0228 degrees (lat)and .0280 degrees(long) is correct So, I want this calculation to be dynamic and work for all zooms   so I'm using (cos Latitude x 111111) / 2^Zoom(13) = 10.72095   for longitude I'm using 111111/2^13 = 13.56   This is the same ratio as well so I'm on the right track!   but how do I use these values in a calculation to add or subtract degrees from the centre coordinates for lat and long to get the coordinates for the corners of the bounding box. any help is appreciated, and I do mean that.


osm2pgrouting hangs on "classes table created"

I'm trying to run osm2pgrouting and on Ubuntu 12.04...everything looks like it's working until it gets to "classes table created" when it just stops. I'm watching the process with the system monitor and it looks like it's loaded the whole OSM file into memory(the RAM used by the program is about the same size as the file, ~200MB). But once it gets to that part the CPU usage goes down to nothing and it doesn't do anything. The program doesn't crash or anything, it just seems to go on break. Here's my command:               osm2pgrouting -file file.osm -dbname osm -user name -conf mapconfig.xml -clean -passwd xxx      Help?


Automatic attribution of one layer from another based on spatial relationship?

I have two layers with a 1:many relationship. Working within ArcMap, I'd like to have that relationship somehow formalized so that when I add a new feature to the child layer, it automatically gets an attribute from the parent, so the link is automatically sustained. For example, say I have a county layer and a site layer. Sites are all within Counties and I want that site layer to have an attribute that indicates which county each site is within. I want to be able to edit the site layer, adding a new polygon, and have that polygon automatically attributed with the county. I thought for a moment that Relationship Classes in a File Geodatabase would do the trick... but I created the relationship class and tried adding a polygon to the site layer. The relationship field remained Null. Seems like a common need that should have an existing method...?


Database has duplicate values after running pgrouting

I am a newbie with postgresql and sql statements so maybe it is a trivial question, I'm sorry for that. I am working on a postgis database and try to use the pgrouting function. My goal is to store the results of the shortest path query in a different table than the original one, which is working so far. The problem is, that it keeps adding the results to the original table too, so there are duplicate values in it afterwards, which I try to avoid but without success so far. I don't know if it should be like this? Anyway can you suggest any solutions to this problem? (I solved it so far so that I delete the duplicate values afterwards, but I really want my database to stay unedited... is it even possible?)   I am using postgresql 8.4 with postgis 1.5 and pgrouting 1.05   This is my query:                  INSERT INTO     route (          SELECT     topo.id,     topo.osm_id,     topo.osm_name,     topo.osm_source_id,     topo.osm_target_id,     topo.clazz,     topo.flags,     topo.source,     topo.target,     topo.km,     topo.kmh,     topo.cost,     topo.reverse_cost,     topo.x1,     topo.y1,     topo.x2,     topo.y2,     topo.geom_way,     topo.available          FROM     Shortest_path('select     *     from     testro_2po_4pgr',     2345,     9234,     false,     true)     AS path,     testro_2po_4pgr     AS     topo     WHERE     path.edge_id=topo.id);      Thank you very much in advance!


How to create a generalized polygon layer from a raster?

I have a tiff file where I have extracted vegetation in a height interval from LIDAR. At the moment the picture is kind of blurry with no data cells between vegetated cells. I would like to create a polygon layer out from this to be used as a mask on sat images with sharp boundaries. I am working with ArcMap is this possible? I have been thinking of running a smoothing tool and then make vector, but the kernel size is to small in Arcmap, I have a resolution of about 1 meter. I would need to use the majority filer in Arcmap many times.. Any ideas how to solve this?


How to make a dynamic animated movement for the graphics on the Silverlight website?

I have some graphic points in one graphicLayer on the map and I want to move their positions to the new places every 5 seconds based on some criteria. And these movement can be visualized dynamically on the website. I'm using ESRI Silverlight API. How should I do that? It seems the map won't update its UI until the graphics' last movement were finished. Should I create a new thread to fulfill this dynamic visualization or there is any other trick? Thanks, Wei


Comparison of three contour lines

I am looking for a way to spatially quantify the difference between three contour line shapefiles. More specifically, I have two elevation rasters which I intend to create contour lines from, but before doing so I would like to compare them to a reference contour line and see if there is any need to revise the input rasters. I understand that I could go the other way and use the Topo to Raster feature in ArcMap and then compare using the Raster Calculator, however I believe I will have an easier time (and explaining to others) doing so the way I originally intended. I have ArcMap 10.1 and Surfer 11. Thank you ahead of time.


How to reproject Network Dataset from GCS_WGS_1984 to Web Mercator?

I need to know how to change the coordinate system of my feature dataset with its network dataset from **GCS_WGS_1984** to **Web Mercator**. Once I know how to do this, I would like to make a tool in Python or ModelBuilder because I need to do it many times.


How to label counties in Mapserver?

I'm fairly new to Mapserver and I was able to get US County boundaries to plot. Is there a way to get the County Name to plot in the center of the county? I've searched around and couldn't find any examples of doing this. Perhaps theres a better alternative that I haven't thought of. Thanks


Splitting Linestrings on the dateline with OpenLayers

A couple of years ago I posted a questions titled "The International Date Line wrap around" @jdeolive suggested I split the features at the dateLine. So I tried. So when I try to split my satellite track with splitWith on the dateline i get back `null`. I know I'm splitting correctly because when I split on Greenwich line I get the expected results. **Anyone know how I can properly split aLinestring programmatically along the date line with OpenLayers?** I would much appreciate example code if you have it. I've tried `wrapDateLine` but it doesn't seem to be working on vector layers despite my vector layer being like this:               vectorLayer = new OpenLayers.Layer.Vector("GroundTracks", {         renderers: ['Canvas', 'VML'],         wrapDateLine: true}); // <-- shoud be wraping.      ![enter image description here](http://i.stack.imgur.com/QfMAS.png) Here's my code:               var features = [];     var format = new OpenLayers.Format.WKT({         'internalProjection': map.baseLayer.projection,         'externalProjection': prjGeographic     });     var satTrack = format.read("LINESTRING (95.538611 13.286511, 94.730711 16.908947, 93.901095 20.528750, 93.043594 24.145177, 92.150978 27.757436, 91.214579 31.364666, 90.223791 34.965899, 89.165364 38.560019, 88.022401 42.145679, 86.772901 45.721205, 85.387568 49.284424, 83.826433 52.832413, 82.033480 56.361087, 79.927797 59.864504, 77.388419 63.333664, 74.227306 66.754285, 70.139140 70.102478, 64.605267 73.335774, 56.712904 76.373458, 44.881134 79.052803, 26.939886 81.047314, 02.704174 81.839241, -21.686285 81.101751, -39.887660 79.141947, -51.906937 76.480894, -59.912477 73.452897, -65.514482 70.225089, -69.645366 66.880243, -72.834535 63.461797, -75.393132 59.994131, -77.512464 56.491789, -79.315407 52.963919, -80.884039 49.416549, -82.275114 45.853820, -83.529088 42.278691, -84.675583 38.693355, -85.736827 35.099503, -86.729876 31.498490, -87.668095 27.891443, -88.562176 24.279331, -89.420849 20.663020, -90.251389 17.043303, -91.059999 13.420926, -91.852092 09.796602, -92.632515 06.171020, -93.405728 02.544857, -94.175960 -01.081217, -94.947343 -04.706542, -95.724045 -08.330456, -96.510402 -11.952298, -97.311065 -15.571400, -98.131162 -19.187081, -98.976502 -22.798638, -99.853829 -26.405335, -100.771148 -30.006378, -101.738172 -33.600889, -102.766925 -37.187866, -103.872602 -40.766117, -105.074803 -44.334175, -106.399366 -47.890158, -107.881153 -51.431559, -109.568417 -54.954914, -111.529886 -58.455253, -113.866668 -61.925160, -116.733085 -65.353081, -120.374635 -68.720132, -125.199754 -71.993642, -131.916790 -75.113368, -141.772276 -77.960803, -156.750096 -80.294831, -178.475596 -81.673196, 156.248392 -81.611421, 135.042323 -80.136505, 120.556535 -77.748172, 111.014840 -74.872356, 104.485504 -71.737081, 99.775637 -68.454400, 96.208126 -65.081545, 93.391438 -61.649716, 91.089380 -58.177038, 89.152970 -54.674643, 87.484294 -51.149703, 86.016609 -47.607042, 84.702947 -44.050030, 83.509299 -40.481112, 82.410411 -36.902133, 81.387093 -33.314533, 80.424442 -29.719485, 79.510644 -26.117981, 78.636145 -22.510889, 77.793053 -18.898997, 76.974710 -15.283040, 76.175371 -11.663718, 75.389950 -08.041709, 74.613831 -04.417680, 73.842693 -00.792294, 73.072378 02.833789, 72.298749 06.459907, 71.517566 10.085391, 70.724342 13.709564, 69.914194 17.331733, 69.081655 20.951185, 68.220447 24.567170, 67.323194 28.178891, 66.381031 31.785476, 65.383084 35.385943, 64.315735 38.979152, 63.161579 42.563725, 61.897893 46.137940, 60.494337 49.699551, 58.909396 53.245525, 57.084691 56.771602, 54.935577 60.271560, 52.334964 63.735923, 49.084320 67.149569, 44.859585 70.487030, 39.107498 73.702694, 30.852243 76.709182, 18.420695 79.329532, -00.339911 81.212453, -25.028018 81.831766)");          var featGreenwichLine = format.read("LINESTRING(0 -89, 0 89)");     var featDateLine = format.read("LINESTRING(180 -89, 180 89)");          features.push(featGreenwichLine);     features.push(featDateLine);     features.push(satTrack);          var resultsGreenwich = satTrack.geometry.splitWith(featGreenwichLine.geometry);     var resultsDateLine = satTrack.geometry.splitWith(featDateLine.geometry);          console.log(resultsGreenwich); //<--RETURNS EXPECTED RESULTS.     console.log(resultsDateLine);//<--RETURNS NULL.          vectorLayer.addFeatures(features);      My question is not a duplicate of this question because they want to know how to do it in ogr2ogr # Update: This is what a typical dataset I work with looks like (24 hour satellite track): The Linestring wkt can be found HERE. ![enter image description here](http://i.stack.imgur.com/pI62J.png)


How can I change what port ArcGIS Server listens on?

I have ArcGIS Server installed with a web adapter on one server. It uses port 80. I want to install another ArcGIS Server on a different server, but I want it to listen on a different port other than 80, such as 8080 or something. How would I do this?


How to fix contour lines which look like a mirror image of the DEM?

I was trying to create contour lines in QGIS 1.8 for a DEM I have, but it's creating it in reverse. The contour lines are sitting on top of my DEM like a mirror image. I was wondering if someone could tell me what I'm doing wrong. I would post a image to show what I mean but the site is not letting me...


How to generate bounding box based on tile numbers using slippy map tiles method?

Description: I am writing a map cache server for my company. I have to get input data based on tms standard and send a request to wms server to render and cache map files. I am using slippy map tiles formula to convert x,y,z to latlon. (North West) Also for finding the other corner (south East), I am converting x+1 and y+1 to degrees. We are using srs 4326 My problem: It works basically, but the map files are a little scaled up! in lower zoom levels, the problem is very obvious. Any help is much appreciated.


Selecting features by location based on selected feature using ArcObjects?

I am very new to ArcGIS and ArcObjects. I am writing a code for a button that will detect a selected feature and then select other features based on the feature that I had selected please take a look at my code               public class LandmarkBtn : ESRI.ArcGIS.Desktop.AddIns.Button {              public LandmarkBtn() {         }              protected override void OnClick() {              var doc = ArcMap.Document;             var focusMap = doc.FocusMap;             IEnumLayer layer = focusMap.get_Layers(null,true);             ILayer lyr = null;             IFeatureClass Lmarks = null;                  while ((lyr = layer.Next()) != null) {                      var featureLayer = lyr as IFeatureLayer;                 if (featureLayer == null)                     continue;                              var name = featureLayer.FeatureClass.AliasName;                      if ("landmarks".Equals(name.ToLowerInvariant())) {                               Lmarks = featureLayer.FeatureClass;                     break;                 }             }                  if (Lmarks == null) {                 MessageBox.Show("Sorry, No LM Layer Found");                 return;             }                       var selection = (IEnumFeature)focusMap.FeatureSelection;             IFeature ftr = null;             ftr = selection.Next();      ftr now holds the selected landmark(feature), I want to perform a query that will select features from another layer that are within 100 meters of the landmark feature, can you please direct me onto where I should look or provide me with a sample code that might help?


Unicode Decode Error for shapefile in Python

I have Python script for converting shapefiles to Geojson. My code works well if I use some usa data, but when I want to use some other encoding, it gives me this error: > Traceback (most recent call last): File > "C:\Python33\lib\tkinter__init__.py", line 1475, in **call** return > self.func(*args)   >  File "C:/Users/name/PycharmProjects/desktopApp/core.py", line 105, in > shp2geojson for sr in reader.shapeRecords():   >  File "C:\Python33\lib\shapefile.py", line 553, in shapeRecords for rec in > zip(self.shapes(), self.records())]   >  File "C:\Python33\lib\shapefile.py", line 525, in records r = > self.__record() File "C:\Python33\lib\shapefile.py", line 501, in __record > value = u(value) File "C:\Python33\lib\shapefile.py", line 60, in u return > v.decode('utf-8') > > UnicodeDecodeError: 'utf-8' codec can't decode byte 0xe1 in position 10: > invalid continuation byte How to fix this problem?                 import shapefile       import json            def shp2geojson():                  filename = askopenfilename()             reader = shapefile.Reader(filename)             fields = reader.fields[1:]             field_names = [field[0] for field in fields]                         buffer = []                  for sr in reader.shapeRecords():                 atr = dict(zip(field_names, sr.record))                 geom = sr.shape.__geo_interface__                 buffer.append(dict(type="Feature", \                                    geometry=geom, properties=atr))                       geojson = open('shp.json', "w")             geojson.write(dumps({"type": "FeatureCollection", \                                  "features": buffer}, indent=2) + "\n")             geojson.close()


Examples of ASCII-art maps

According to Wikipedia, ASCII-art is one of the earliest techniques used for digital graphical design. An ASCII-art technique can be traced back to 1939 and computer-art pioneers have used it since 1966. Nowadays ASCII art can be found in info files, console applications, non-graphic computer terminals and etc. Around the Web one can see various beautiful examples of ASCII art, but not as that impressive examples of maps. Do you think that ASCII-art is just far too unsuitable for cartographic purposes? If not, can you post examples of an ASCII-art map?


Change projections depending on the zoom level

Is it possible in ArcGis (from a technology/performance/… point of view) to switch projections depending on the zoom level? For example, Is it possible when zooming at some extent to the poles, my projection to be switched from the "Miller projection" to "stereographic projection". For polar areas, a stereographic projection is best.


Python scripts runs from PythonWin but not ArcCatalog (ArcGIS 10)

I add a field to the target FeatureClass it is not present, via arcpy.AddField_management(...). Works fine from PythonWin, but the AddField call fails when the script is run from ArcCatalog. I have this exception catch code:               except Exception as ErrorDesc:         Errors = "TRUE"         arcpy.AddMessage("An unknown error occurred:")         arcpy.AddMessage(ErrorDesc.message)      But the error I get is at the end of this output:               Getting list of fields.     Adding PC field to target.     An unknown error occurred:     Object: Tool or environment <摁䙤敩摬浟湡条浥湥t> not found      And that Mandarin text - is that unicode being mangled?


Geographic limit to overlay analysis in geoprocessing service

**Function:** I've created a geoprocessing service that serves a toolbox containing a custom python tool. This python tool selects a polygon and buffers it by 1 mile. This buffer is then used to intersect with another polygon layer to produce a list of features in the overlay. Pretty simple. **Environment:** The same geoprocessing service is re-created four times [three Oracle environments and four GIS web applications]. **Error:** In three of four gp services, when this tool is used at a REST endpoint -- _and when the overlays is in a specific geographic region_ [roughly 250 sq. miles]-- this error is produced: “Invalid Topology [Cannot read input cache.] Failed to execute (Intersect). Failed to execute (ToolCustomIntersect)” **Fix:** I've debugged a bazillion ways and have come up with one solution: re-create the GP service with a different name (as improbable a fix as this seems). **What just happened!?!** The only pattern that I've deduced through various tests is that names of GP services containing a high redundancy of letters in a complete pathname or the length of the name resulted in this error. **The kicker** is when I run the same tool in AC on the AGS server it works. Meaning I'm not utilizing the gp service or the REST endpoint. No topology or cache error. So, there is something about the GP service that is producing a geographic limitation to an overlay tool. Quirk? Or real issue. I'd love your ideas and comments.


Eliminate small polygons from shapefile

I downloaded GTOPO30 `*.DEM` files, and extracted a contour line at 2000m altitude using `gdal_contour`. In the resulting shapefile, I have many small polygons in areas where the altitude is close to that contour line, and the image looks quite noisy. How can I, preferably using gdal/ogr or QGis, somehow 'downsample' these contours, so that the picture looks cleaner? I basically want to eliminate all small features. PS: One way would be to downsample the grid before doing the contour extraction; is this the way to go, or should i rather downsample the shapefile?


pdf google maps export

In my php+postgis+geoserver+OL application I have to export a map in a pdf file. This map has two layer: the base is a google map layer and a vector layer as overlay. Is there a way to make a pdf like this?


Create a single line from a resultset of line segments

How can I create a single line using the line segments geometry found in each row in resultset? I followed this tutorial: http://anitagraser.com/2013/07/06/pgrouting-2-0-for- windows-quick-guide/ I found roads in a route from point A to point B. This roads are rows in a resultset and now I need to create a single line from point A to point B representing the entire route.


ArcToolbox Usage ArcGIS 10.2

Why is it when you right-click to open some of the tools on the Arc Toolbox, such as the TIN to Raster Tool for example, an image of a red x immediately appears over the tool icon? The tool dialog then never opens. What am I not understanding?


Looking for a fast, open-source raster cost-distance function to use in code

I've been scouring the internet for a fast, open-source cost-distance function that I can embed inside my code. The functionality should basically work like the ArcGIS implementation where I can specify a source raster and cost raster and output a cost distance raster. That said, the implementation does not need to be as sophisticated as ArcGIS in that I don't need to necessarily input "rasters" with embedded geo metadata - a signature that takes simple numeric arrays will suffice since I can verify that the data overlaps correctly at the time I call the function. My specific intent is to calculate the cost-distance to a single point in the center of a 1000 x 1000 cost raster based on a user click, so fast execution is very important. A C# implementation would be ideal but I'll look at anything that's out there. Does anyone know of an open-source library that supports this? Thanks for your help!


Why might ArcGIS Export to PDF lose polygon?

How can I solve this problem? After exporting my map to pdf (or any other format), the exported map does not show the basic-polygon-layer, but only a blue/turquoise background with line and point features in perfect condition. This did not change after trying different resolutions, data formats and picture compressing methods. I'm using ArcGIS 10.2 Advanced.


How to paint area below certain elevation, using no coding and Google Maps, Google Earth, Bing

How can I show the area below a certain elevation, using Google Maps, Google Earth, Bing Maps or similar end-user application, and no coding? Thanks in advance


How to find out whether a photo is geotagged or not?

I use a android app called OSMTracker. This app records the GPS track and can take pictures and notes. Using JOSM software, the photos are shown exactly at their coordinates (location) but i cannot use these photos in other GIS softwares like QGIS, it says **no geotagged photos in the location**. How can i find out whether a photo is geotagged or not? I know that the information is written in some EXIF header, but i don't have any other files. I only have the GPS track and the photos. If the photos are not geotagged, can i geotag them using the GPS track?


SelectFeature not working in OpenLayers

I'm still sort of new to openlayers, but I've been able to set up a map which reads in a KML, loops through the different regions contained therein, and draws those polygons on a vector layer overtop of an OSM layer. This all works fine until I try to add a control. All I want to do is trigger an function when the polygon is clicked. For testing purposes, right now I'm just trying to trigger an alert.   The applicable pieces of my code are below:               function onFeatureSelect(feature){         alert("boom");     }          function onFeatureUnselect(feature){         alert("unBoom");     }     var selectControl;     map = new OpenLayers.Map(divName, {         controls: [new OpenLayers.Control.Navigation(), new OpenLayers.Control.LayerSwitcher(), new OpenLayers.Control.PanZoomBar(), new OpenLayers.Control.Attribution()],         projection: googProj,         units: 'm',         maxResolution: 156543.0399,         numZoomLevels: 10     });     var layerOSM = new OpenLayers.Layer.OSM();     map.addLayer(layerOSM);     var layerVector = new OpenLayers.Layer.Vector("KML Regions");          $.each(rPoly, function(){  //Looping through the data         var feature_polygon = new OpenLayers.Feature.Vector( //We'll make a polygon from a linear ring object, which consists of points     new OpenLayers.Geometry.Polygon(new OpenLayers.Geometry.LinearRing(this)), {             "rName": thisR         }, {             'fillColor': thisC,             'strokeWidth': borderWidth,             'strokeColor': borderColor,             'fillOpacity': thisO         });         layerVector.addFeatures([feature_polygon]);     });          map.addLayer(layerVector);     selectControl = new OpenLayers.Control.SelectFeature(layerVector, {         onSelect: onFeatureSelect,         onUnselect: onFeatureUnselect     });     selectControl.activate();     map.addControl(selectControl);      Please remember that everything renders fine, I just can't get a function to fire when a polygon is clicked. Any help would be GREATLY appreciated. I'm getting pretty frustrated since this should be something fairly easy to do. Thanks. **UPDATE** When I try using getLeyersByName to get the "KML Regions" layer, it comes back empty. How is this possible since all of the polygons are visible? Could this be part of the issue? **UPDATE OF SHAME** What it actually turned out to be is that I had the loop creating the features on the layer running from a function and then I'd pass the fully rendered layer back. This was causing an error. So, in trying to simplify the code for the question, it seems like I fixed it if I would just paste it back in. The code would have died anyway due to the calls being out of sorts, so I marked that answer as solving the problem. Thanks everyone.


Cluster Strategy different Labeling at Different Level

**what I did?** I am trying to plot some points using cluster strategy of openlayer using animatedCluster plugin. I have gson data as given:               {       "type": "FeatureCollection",       "features": [         {           "type": "Feature",           "id": "SITESECTOR.1",           "geometry": {             "type": "Point",             "coordinates": [               83.01156083999999,               29.12400297             ]           },           "geometry_name": "SP_GEOMETRY",           "properties": {             "siteid": "S3 ",             "zone": "Z1 ",             "district": "D1 ",             "MI_STYLE": null           }         },         {           "type": "Feature",           "id": "SITESECTOR.2",           "geometry": {             "type": "Point",             "coordinates": [               82.60901315999999,               28.707924959999996             ]           },           "geometry_name": "SP_GEOMETRY",           "properties": {             "siteid": "S8 ",             "zone": "Z8 ",             "district": "D8 ",             "MI_STYLE": null           }         },         {           "type": "Feature",           "id": "SITESECTOR.3",           "geometry": {             "type": "Point",             "coordinates": [               83.917305,               29.00006496             ]           },           "geometry_name": "SP_GEOMETRY",           "properties": {             "siteid": "S4 ",             "zone": "Z2 ",             "district": "D2 ",             "MI_STYLE": null           }         },         {           "type": "Feature",           "id": "SITESECTOR.4",           "geometry": {             "type": "Point",             "coordinates": [               84.14876916,               28.725629039999998             ]           },           "geometry_name": "SP_GEOMETRY",           "properties": {             "siteid": "S5 ",             "zone": "Z3 ",             "district": "D3 ",             "MI_STYLE": null           }         },         {           "type": "Feature",           "id": "SITESECTOR.5",           "geometry": {             "type": "Point",             "coordinates": [               83.50468884,               28.58398497             ]           },           "geometry_name": "SP_GEOMETRY",           "properties": {             "siteid": "S6 ",             "zone": "Z6 ",             "district": "D6 ",             "MI_STYLE": null           }         },         {           "type": "Feature",           "id": "SITESECTOR.6",           "geometry": {             "type": "Point",             "coordinates": [               83.08200887999999,               29.40729102             ]           },           "geometry_name": "SP_GEOMETRY",           "properties": {             "siteid": "S1 ",             "zone": "Z1 ",             "district": "D1 ",             "MI_STYLE": null           }         },         {           "type": "Feature",           "id": "SITESECTOR.7",           "geometry": {             "type": "Point",             "coordinates": [               82.73984112,               29.159415             ]           },           "geometry_name": "SP_GEOMETRY",           "properties": {             "siteid": "S2 ",             "zone": "Z1 ",             "district": "D1 ",             "MI_STYLE": null           }         },         {           "type": "Feature",           "id": "SITESECTOR.8",           "geometry": {             "type": "Point",             "coordinates": [               83.24302895999999,               28.619397             ]           },           "geometry_name": "SP_GEOMETRY",           "properties": {             "siteid": "S7 ",             "zone": "Z7 ",             "district": "D7 ",             "MI_STYLE": null           }         }       ],       "crs": {         "type": "EPSG",         "properties": {           "code": "4326"         }       }     }      I am trying to **group these by it's property like zone or district** which are its attributed as well as other polygons and style it approprietly. And when there is only a single feature I wanted to label it with siteid. I tried without animated cluster and with Bbox strategy the labeling is fine but when i add animated cluster it all fails with **undefined** label. My code:               var map;                           // Define three colors that will be used to style the cluster features                 // depending on the number of features they contain.                 var colors = {                     low: "rgb(181, 226, 140)",                      middle: "rgb(241, 211, 87)",                      high: "rgb(253, 156, 115)"                 };                      // Define three rules to style the cluster features.                 var singleRule = new OpenLayers.Rule({                      filter: new OpenLayers.Filter.Comparison({                                         type: OpenLayers.Filter.Comparison.EQUAL_TO,                                         property: "count",                                         value: 1                                     }),                              symbolizer: {                         fillColor: colors.low,                         fillOpacity: 0.9,                          strokeColor: colors.low,                         strokeOpacity: 0.5,                         strokeWidth: 12,                         pointRadius: 10,                         label: "${siteId}",                         labelOutlineWidth: 1,                         fontColor: "#ffffff",                         fontOpacity: 0.8,                         fontSize: "12px"                     }                 });                      var lowRule = new OpenLayers.Rule({                     filter: new OpenLayers.Filter.Comparison({                         type: OpenLayers.Filter.Comparison.BETWEEN,                         property: "count",                         lowerBoundary: 2,                         upperBoundary: 15                     }),                     symbolizer: {                         fillColor: colors.low,                         fillOpacity: 0.9,                          strokeColor: colors.low,                         strokeOpacity: 0.5,                         strokeWidth: 12,                         pointRadius: 10,                         label: "${count}",                         labelOutlineWidth: 1,                         fontColor: "#ffffff",                         fontOpacity: 0.8,                         fontSize: "12px"                     }                 });                 var middleRule = new OpenLayers.Rule({                     filter: new OpenLayers.Filter.Comparison({                         type: OpenLayers.Filter.Comparison.BETWEEN,                         property: "count",                         lowerBoundary: 15,                         upperBoundary: 50                     }),                     symbolizer: {                         fillColor: colors.middle,                         fillOpacity: 0.9,                          strokeColor: colors.middle,                         strokeOpacity: 0.5,                         strokeWidth: 12,                         pointRadius: 15,                         label: "${count}",                         labelOutlineWidth: 1,                         fontColor: "#ffffff",                         fontOpacity: 0.8,                         fontSize: "12px"                     }                 });                 var highRule = new OpenLayers.Rule({                     filter: new OpenLayers.Filter.Comparison({                         type: OpenLayers.Filter.Comparison.GREATER_THAN,                         property: "count",                         value: 50                     }),                     symbolizer: {                         fillColor: colors.high,                         fillOpacity: 0.9,                          strokeColor: colors.high,                         strokeOpacity: 0.5,                         strokeWidth: 12,                         pointRadius: 20,                         label: "${count}",                         labelOutlineWidth: 1,                         fontColor: "#ffffff",                         fontOpacity: 0.8,                         fontSize: "12px"                     }                 });                      // Create a Style that uses the three previous rules                 var style = new OpenLayers.Style(null, {                     rules: [singleRule,lowRule, middleRule, highRule]                 });                         function init() {                          map = new OpenLayers.Map('map');                     var wms = new OpenLayers.Layer.WMS(                         "District Band", "/geoserver/wms/",                         {layers: 'data:ICT_BND'}                     );                          var layer = new OpenLayers.Layer.Vector("WFS", {                                             protocol: new OpenLayers.Protocol.WFS({                             version: "1.1.0",                             url:  "/geoserver/wfs",                             featurePrefix: 'data', //geoserver worspace name                             featureType: "sites",                             featureNS: "www.wru.scl.com",                             geometryName: "SP_GEOMETRY"                          }),                         //new OpenLayers.Strategy.Fixed()                           strategies: [                                             new OpenLayers.Strategy.BBOX(),                                             new OpenLayers.Strategy.AnimatedCluster({                                                 distance: 45,                                                 animationMethod: OpenLayers.Easing.Expo.easeOut,                                                 animationDuration: 10                                             })                                       ],                         styleMap:  new OpenLayers.StyleMap(style)                          });                     map.addLayers([wms, layer]);                     map.setCenter(new OpenLayers.LonLat(85.522137, 27.629811), 10);      Intended Result: **Different labelling at differnt points. First the label should be zone and then district and then siteid** I am trying really hard to achieve this is this possible? Thank you for help.


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How can I change the class of one pixel in a classified image?

I have a classified image (I did it in ERDAS) with six categories. There are some misclassified pixels (especially high-density urban category). Is there any way that I can choose one pixel and then change its class (for instance change bareland to high-density urban) in ERDAS or Arcmap? I do appreciate your help. Thanks.


Custom imagery not converted correctly in web Bing format tile with Global Mapper?

I have Custom image and I converted to that to the web bing format tiles with the help of global mapper but that are not produce correct quad key in each tile. On the bing map quad key is starte like "0231101100132" And I have custome imagery of same area and I tried to convert that converted to "0231111002013013" So here you can see in bing 02311011... and in the custom tiles that I have created is started from 0231111... So that will not fit the correct area can anybody help on this then that would be very appreciated.


How to get the distance from a point to the nearest line string?

I am trying to use st_distance to find the nearest line string to a point. I have two tables in cartodb one is a table of points and the other table is poly lines. To see if I had the logic right I did a st_distance query on the points table from a lat,long point. Everything worked as planned. Then I tried creating a query that would find the closest polygon from a point in my point table. The error I am getting is this "cross-database references are not implemented: cartodbpoint.the_geom.stdistance" and the query I am trying out is:                   SELECT cartodbpoint.cartodb_id,         MIN(cartodbpoint.the_geom.STDistance(cartodbline.the_geom)) as MinDistance         FROM cartodbpoint, cartodbline         GROUP BY cartodbpoint.cartodb_id      My goal is to get the distance from that point to the nearest line string.


Rendering points and polygons with Mapnik

I've tried to render a few maps in Mapnik and I have a little problem. I want to render a map that contains two layers: point and polygon. I've used this script:               import mapnik     rule = mapnik.Rule()     rule.symbols.append(mapnik.PolygonSymbolizer(mapnik.Color("darkgreen")))     rule.symbols.append(mapnik.PointSymbolizer())     style = mapnik.Style()     style.rules.append(rule)     layer = mapnik.Layer("mapLayer")     layer.datasource = mapnik.Shapefile(file="polska.shp")     layer.styles.append("mapStyle")     map = mapnik.Map(640, 480)     map.background = mapnik.Color("white")     map.append_style("mapStyle", style)     map.layers.append(layer)     map.zoom_all()     mapnik.render_to_file(map, "map.png", "png")      There is only one shapefile to render, but that is my problem. When I'm adding the 4th line `rule.symbols.append(mapnik.PointSymbolizer())`, I always get rendered polygons with additional points (centroids of each object I guess): ![enter image description here](http://i.stack.imgur.com/O4rmx.png) Why are there black points? Is there any possibility to render two layers (polygons and points) at the same time, without these centroids? What am I doing wrong?


Updating a feature class

I am working on ArcGIS 10.2.1. I have a feature class containing more than 4000 records and a table having approximately 1000 records. Both feature class and table have some common fields however, with different values in them. Feature class is in ArcSDE geodatabase and table is in file geodatabase. We want to update feature class's fields with the values in table. There are multiple fields (100 above). I was thinking of joining these two and then use field calculator but as records in feature class are more than the table and there are multiple fields which I want to update. Is there any python script or tool I can use to update the feature class values from the table?


Scratch workspace for ArcGIS Desktop: file name conflict for multiple users

I have installed ArcGIS Desktop on a server (it is not ArcGIS Server installation) where I want to give access to users to use toolbar (developed using Python-Addins) that I have developed. All intermediate files are written to a folder "C:/Temp" (I am not specifically writing those but only have specified scratch folder to be "C:/Temp"). If multiple users access it simultaneously, will there be a file naming conflict inside "C:/Temp"? If yes, is there any solution to it (how do I make file names unique even if multiple users are doing the same process or running same function at a moment)?


XY data --> NAD_1983_2011_California_Teale_Albers always fails?

In ArcGIS 10.2, I am importing XY (point) data from excel, and have been having trouble projecting it into the following Projected Coordinate System: NAD_1983_2011_California_Teale_Albers -- NAD 1982 (2011) California (Teale) Albers (Meters) WKID: 102962 Authority: ESRI The program does not throw errors on conversion, but always crashes after I exit the program and try to reload (Add) the new projected shapefiles. I have tried the following workflows, and each results in the same outcome:   1. Simultaneously defining the Geographic Coordinate System and Projected Coordinate System.   2. Defining the GCS, then saving as a geodatabase, then assigning the PCS (with "Project") As for the choice of GCS, I have tried both NAD 1983 (GCS_North_American_1983) and WGS 1984 (GCS_WGS_1984). Is there something I'm just not getting about projections, or is there potentially an error in the way this projection is created. I chose this PCS because I'm using only California data and I'm primarily interested in distance, rather than angle or area data. Thanks!


Renaming Feature Class within versioned Feature Dataset

I am working in ArcSDE. I have several feature datasets within an Oracle Enterprise Geodatabase. When I try to rename one of the feature classes that is within a feature dataset it "falls out" of the dataset, it is now just floating in the geodatabase on its own. And now the rest of the feature dataset is inaccessible, when I try to open it I get an error saying "Layer not found" and referencing the feature class that I tried to rename. Am I violating some rules of ArcSDE that I am not familiar with? Thanks.


Show names once on a dual carriageway in Tilemill

I am trying to render a local map using OSM data with Tilemill. I have things very close to how I want them. The biggest issue I would like to resolve is having road names show up twice for dual carriageway. I was thinking I could use oneway="1" plus another selector to have it only render on "odd" streets but could not figure a way to make this work. Here is my css:               #osm.roads[type="trunk"],     #osm.roads[type="primary"] {       ::label {         text-name: [name];         text-face-name: 'Droid Sans Regular';         text-placement: line;         text-size: 15;         text-dy: 12;         text-halo-fill: fadeout(white, 30%);         text-halo-radius: 2.5;         text-max-char-angle-delta: 17;         text-min-distance: 5;       }     }      ![enter image description here](http://i.stack.imgur.com/coTSQ.png)


ArcMap 10.1 Crashing when using field calculator

I keep getting a serious error message when I try to use the field calculator. I've joined a .csv to my SDE feature class and am trying to set one of the columns equal to one of the columns from the .csv. But it keeps crashing! Is this happening to anyone else?