8
votes
3answers
5k views

Displaying dynamic table in Data Driven Pages environment?

I am creating a map series that has many polygons per sheet. There is annotation for the polygons however some polygons are very small with no annotation for them (annotation would completely hide a ...
27
votes
4answers
14k views

Joining non-spatial CSV file to spatial data (shapefile) using QGIS?

I have a CSV file which has postcode data in a field, but it is non-spatial e.g. no Easting and Northing. I have a shapefile with postcode in a field and some additional data. I want to join the ...
13
votes
4answers
3k views

Elevation profile 10 km each side of a line

How can I get an elevation profile for a band of terrain? The highest elevation within 10 km (on each side of the defined line) should be taken into account. I hope my question is clear. Thank you ...
6
votes
5answers
6k views

How to calculate distances in a point sequence?

I'm looking for help calculating the distance between a sequence of points that are in a single Shapefile in QGIS. Below is what my data look like and a blank distance column I've added to show how ...
21
votes
2answers
16k views

How to convert .shp into .gpx using QGIS?

I'm newbie using QGIS. I would like to convert .shp into .gpx. So, using Qgis, I open my shapefile and I tried to "save as" gpx but it gives an OGR error: creation of field ObjectId failed (OGR ...
14
votes
2answers
4k views

How can I create weighted Thiessen polygons?

I have a point shape file and I create Thiessen (Voronoi) polygons programmatically using this scripting syntax: CreateThiessenPolygons_analysis (in_features, out_feature_class, fields_to_copy) ...
13
votes
5answers
16k views

Creating point file along line (trail) at regular distances (0.20 miles) using ArcGIS Desktop?

I'm using ArcGIS 10.1. I have a trail network that I'm trying to establish signs along the trails every 0.20 miles. Is there a way to create the point file from the line feature?
12
votes
8answers
5k views

ArcObjects Resources [closed]

What are the best books/web sites for C# development with ArcObjects? The ArcGIS Resource Center is very helpful, but I am trying to find sources with more examples.
9
votes
6answers
8k views

How to fix quickly a lot of geometry validity errors in QGIS?

I am working on ownership data at a US county level. I have one shapefile per county that contains thousands of tax parcels. I need to dissolve the polygons representing parcels owned by the same ...
13
votes
3answers
6k views

How to programatically check for a mouse click in QGIS

I want to know how to check for a mouse click in QGIS. I am trying to write a python plugin and want to provide functionality similar to the "Select Single Feature" tool that already exists in QGIS. ...
6
votes
1answer
2k views

How to evaluate raster calculator expressions from the console?

How can I execute from the console an expression that should be used with the raster calculator? I'm searching for something like this: qgis.someRasterCalcClass.evaluate("boh@1 + boh@2", ...
15
votes
4answers
2k views

algorithm to place maximum number of points within constrained area at a minimum spacing

I have a polygon layer that describes a constraint; I wish to add points within this area. I want to add as many points as possible, but they must have a minimum spacing between them. Is it possible ...
5
votes
1answer
731 views

Calculate population within radius

I have population data matched with polygons and a set of points that I have drawn buffers around. Assuming that the population within each geographical area, i.e. the polygons, is evenly distributed, ...
4
votes
2answers
859 views

Is Shooting Star broken in PGRouting 1.05?

I'm using pgrouting DLL 1.05 with postgresql 9.1. All required function installed. Astar and Dijkstra work fine with sample data but "SHOOTING STAR" is not considering "reverse_cost". Also if i try ...
3
votes
1answer
4k views

How do I find vector line bearing in QGIS or GRASS?

How can one extract the bearings from a set of lines in a vector file? I'm trying to find the bearings of several straight vector line segments (simplified contour lines, actually) and can't figure ...
3
votes
5answers
7k views

How to convert LAS to GRID/Raster for ArcGIS input?

I was wondering if there is an option to convert LAS (LIDAR data) to raster or GRID format that ArcGIS could read it.
19
votes
2answers
5k views

Adding new group layer with ArcPy?

Does anyone now how to add a group layer with Python in ArcGIS Desktop 10? I can use arcpy.mapping.AddLayer but surely this is only for an actual layer as opposed to a group layer. so far I have ...
15
votes
7answers
11k views

Recalculating full extent of File Geodatabase feature class?

I have a featureclass in an Esri file geodatabase. When I edit the features using the editor in ArcMap, and I delete most of my features and keeping only the ones in the middle, the zoom to layer ...
14
votes
4answers
8k views

free GIS software that can orthorectify?

Would someone care to recommend a free and/or open source GIS application that can orthorectify map images?
11
votes
3answers
7k views

Google Maps layer copyright popup every time map updated / user input

I have used a Google Maps hybrid layer in Openlayers in my HTML5 iOS app for months now and it worked perfectly. Just recently they changed something because the 'Map data...' line at the bottom looks ...
9
votes
1answer
2k views

How to compute the bounding box of multiple layers in lat/long?

I am writing an application to performance test all kinds of map services, primarily AGS 9.x, AGS 10, and WMS 1.x. Part of the application involves generating random bounding boxes for individual ...
8
votes
6answers
3k views

How to calculate the maximum distance within a polygon in x-direction (east-west direction) in PostGIS?

I am interested in the maximum width of a polygon, e.g. a lake, in the east-west direction. Bounding boxes will help only in simple polygons but not in complex concave polygons.
7
votes
1answer
9k views

Adding automated values to attribute field?

I have parcel and buildings layers. In their attribute tables I want to replace "NULL" values with numbers from 1 to 2000, in "Parcel ID", or "Building ID" field. How can I do this in ArcGIS ...
5
votes
3answers
774 views

Summary table with a field that shows components of each summarized record

I have a table with 2 fields the first is for community and the second for the main community that it belongs to, as in the image I want to summarize the second field (Belongs_to) but with an extra ...
2
votes
3answers
2k views

Data-defined Styles in QGIS

I have downloaded a shapefile of bedrock geology. I need it to be displayed as it should be with the style applied. The supplier will no give me a qml. but i have noticed in the .dbf file the Cyan ...
13
votes
6answers
13k views

How do I create a convex hull in ArcGIS Desktop?

I would like to be able to create a convex hull in ArcGIS Desktop 9.x, but I cannot find an appropriate tool. How does one go about creating one? I am interested in answers for all license levels: ...
11
votes
1answer
7k views

Use python to add layers to TOC

I've been battling with adding layers to the TOC for some time now. I have managed to single layers added but need to loop through a folder and add all layers. Shapefiles I cannot get to add at all. ...
6
votes
1answer
7k views

Invalid Topology [Topoengine error] from ArcGIS for Desktop?

Using ArcGIS 10.1 for Desktop, I'm trying to run the Identity function on two large data sets but it fails every time. I don't think it is a lack of hardware as I can run other processes on the same ...
3
votes
2answers
5k views

Calculate line distances inside of polygons using ArcGIS for Desktop?

I'm working with two data sets: NHD polyline stream layer for my entire state HUC Watershed boundary Polygons for the entire state I am looking for a way to calculate the total length of streams ...
1
vote
1answer
251 views

Graph/Network building and analysis of linked polygons in ArcGIS for Desktop?

This is more of a follow-up question to Divide polygons into *n* number of groups of equal counts with ArcGIS 10.2 and grouping village points based on distance and population size, particularly the ...
15
votes
2answers
4k views

Using Geodesic Measurements for Circle Radii?

I am currently developing an OpenLayers mapping site. Measurements can be made using a line tool, and an area tool. Both of these are currently set to calculate geodesic measurements as outlined in ...
8
votes
1answer
750 views

How to reopen hidden panels in print composer?

I unfortunately deleted the menu (Qgis 1.8.0) in print composer (settings for labels etc) . Now I am wondering how to display it again? The menu is gone in all my projects and I could not find a ...
8
votes
2answers
2k views

Raster generalization - buffers in rasters, expand pixels?

Is it possible to create buffers for pixels of raster files? Actually I need to expand the pixels classified as 1 (in white in the figure) with a spatial range of 1 or 2 pixels, in order to perform ...
3
votes
1answer
133 views

Why isn't the service layer shape properly spread out?

I created a simple service layer polygon in network analyst (ArcGIS Desktop 10.2) with no hierarchies set in the street network. Now I don't understand why is this polygon created along some ...
2
votes
1answer
5k views

Opening Esri Personal Geodatabase (*.mdb) using QGIS?

Is it possible to open an Esri Personal Geodatabase (*.mdb; ArcGIS 10.2) in QGIS 2.6? Previous versions were right.
1
vote
1answer
528 views

Flatten / collapse one-to-many table and keep the 'many' attributes separate

I have a data set that contains intersection data. Each intersection node has up to 6 links which is identified by IN_LINK and OUT_LINK attributes. I want to create a new dataset that includes the ...
1
vote
2answers
293 views

How to define Subroutines and functions?

I am working in VBA. My error is sub and function are not defined. Here is my code: Private Sub CreateMap(cboDistrict As String) Dim mapDocument As New mapDocument If ...
46
votes
7answers
6k views

Best practices for PostGIS production environments?

What PostGIS documentation have you come across that has been helpful when tuning PostGIS for a production environment? I would like to get together with my DBA to setup a Postgresql/PostGIS ...
38
votes
8answers
22k views

Alternatives to ArcGIS Online?

I am considering purchasing ArcGIS Online for a group of users who currently use about 5% of ArcGIS capabilities (ArcMap, simple map creation and information display) about 80% of the time. Primary ...
43
votes
4answers
3k views

What are the FOSS equivalents to these ArcGIS products?

I'm a long-term user of ESRI software, and I now have a need to use free and open source software. I've been reading about Open Layers, PostgreSQL, PostGIS, GeoServer and MapServer but I can't find ...
19
votes
11answers
56k views

List of available online WMS services (Weather, Land Data, Place Names…)

I'm Looking for WMS services freely available to the public to overlay on my application, specifically weather and AIS information. Perhaps this is a good place to list some available online WMS ...
42
votes
6answers
92k views

What are Raster and Vector data in GIS and when to use?

What are raster and vector data in the GIS context? In general terms what applications, processes, or analysis are each suited for? (And not suited for!) In answering someone's question today, I ...
36
votes
6answers
16k views

Downloading OpenStreetMap Data

Is there a straightforward way to download data from OpenStreetMap (OSM)? Using North America as an example, I realize Cloudmade (http://downloads.cloudmade.com/north_america) and geofabrik ...
24
votes
5answers
20k views

Is ArcSDE no longer needed at ArcGIS 10.1?

Through my frustration of not finding the post-installation wizard with ArcSDE 10.1 and being unsuccessful with the command line tool to start an SDE service on our SDE databases, I found I was able ...
24
votes
8answers
8k views

When Versioning with ArcSDE can posted edits be cancelled or rejected?

I am using ArcGIS 9.3.1 and attempting to work with an SDE geodatabase (with one polygon feature class) that has already been registered as versioned. I'm new to versioning and am still trying to ...
23
votes
4answers
18k views

Select bounding box using postgis

I want to create a query to select all ways and their nodes that exist within a bounding box using postGIS. The bounding box shall includes all details as osmosis "--bounding-box" command will ...
26
votes
2answers
16k views

How can I convert data in the form of lat, lon, value into a raster file using R?

I have a data set of values over a km grid in the continental U.S. The columns are "latitude", "longitude", and "observation", e.g.: "lat" "lon" "yield" 25.567 -120.347 3.6 25.832 ...
26
votes
4answers
6k views

How can I switch line direction in QGIS?

Something that is hopefully pretty easy. I would like to be able to swap the direction of a polyline/line in QGIS. I made a custom tool to do this in MapInfo a couple of years ago, however I can't ...
9
votes
3answers
1k views

Why is any pgr_* routing function taking forever based on OSM data in an pgrouting enabled DB

I loaded the German OSM dataset into the pgrouting DB by using osm2po 4.7.7. Everything works fine i have osm2po set up via it's config and it's working like a charm through it's Java part. I had the ...
22
votes
1answer
5k views

Calculating Flow Direction and Delineating Basins from Projected vs. Unprojected DEM Data

This is somewhat of a theoretical question stemming from some discussions with colleagues on the topic of implications with delineating basins with projected (e.g., Albers Equal Area) vs. unprojected ...

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