19
votes
9answers
10k views

Looking for system specifications for a modern GIS workstation

My current employer has given me the opportunity to design my own GIS workstation. The problem is I have no idea what is important when it comes to hardware! I have been given a datasheet from Fujitsu ...
15
votes
3answers
10k views

Listing all feature classes in File Geodatabase, including within feature datasets?

From python how can I build a list of all feature classes in a file geodatabase (*.gdb), including inside feature datasets? The standard example only lists feature classes at the top level of the ...
16
votes
5answers
10k views

Is it possible to make a DEM from contours in QGIS?

Is it possible to make a DEM from contours in QGIS? I have a shp file (contours) and their heights, can I use QGIS for produce a DEM without using GRASS? I find this creating a dem from contours but ...
7
votes
5answers
9k views

How to join multiple records to single feature?

apologies for what I'm guessing is a really easy problem to solve. GIS user, not programmer here. I'm trying to create a join/relate in QGIS where I have a shapefile of buildings and to that I would ...
10
votes
7answers
6k views

How to georeference a vector layer with control points?

I have a non-georeferenced vector layer that I need to be georeferenced. With raster layers the task is easy and straightforward, but I have no idea what should I do with my vector layer. I have a few ...
5
votes
1answer
753 views

Raster incorrectly reprojected to OSGB(27700)

Ubuntu 12.04, QGIS 1.8.0, GDAL/OGR 1.7.3, GEOS 3.2.2 Open a Spatialite db with OS Mastermap poly layer (EPSG:27700); Add OpenLayers Plugin (1.0) from QGIS offical repository; Add a Google Satellite ...
61
votes
19answers
54k views

List of GIS applications for Android Tablets

I know that ArcGIS will someday be available for Android, but does anyone know of any other GIS apps that are available for Android tablets?
43
votes
21answers
47k views

Are there any free administrative boundaries available as shapefiles?

After learning about the US Census's TIGERLines datasets I'm addicted to GIS :) I've working with the following layers, from the USA data Country boundaries State boundaries County boundaries City ...
14
votes
3answers
2k views

Porting Avenue code for Producing Building Shadows to ArcPy/Python for ArcGIS Desktop?

Whuber provided an answer at Producing building shadows? which required using Avenue code. Any idea how to make it work in ArcGIS Desktop 10?
23
votes
10answers
45k views

How to convert MapInfo TAB and/or MIF to SHP using free tools or ArcGIS for Desktop core product?

How do I convert MapInfo TAB and/or MIF files to SHP using only free tools or ArcGIS itself? I've not had much luck trying to do this in the past and I don't want to have to shell out for the ArcGIS ...
32
votes
6answers
10k views

How to use PostgreSQL/PostGIS with ArcGIS for Desktop? [duplicate]

Has anyone used PostgreSQL with PostGIS successfully? I am a semi-experienced ArcGIS user and want to build out a database and connect it to ArcCatalog. I've scoured the internet for resources but ...
10
votes
5answers
22k views

How to add a simple WFS layer from GeoServer to OpenLayers map?

I'm trying to add one of the included datasets with GeoServer to an OpenLayers map. I've followed the OpenGeo tutorials, seen similar thread on here, but I can't seem to crack it. Can somebody take a ...
22
votes
7answers
20k views

Removing small spaces (slivers) between polygons?

I have a set of polygons representing administrative districts. The districts were digitized by hand, and there are small spaces (slivers) between polygons where the polygons should be touching. How ...
21
votes
3answers
20k views

How to clip a raster with vector boundaries?

I am using QGIS. I would like to clip a raster precipitation layer using an admin boundary layer that is vector data. However the geoprocessing tools seem to be usable only for vector data. How can ...
18
votes
3answers
33k views

How to merge multiple layers to one layer using QGIS?

I've imported several shapefiles which where exported from an Mapinfo .tab. Several tab files are imported resulting in 20+ layers. Afterwards I want to export it to geoJSON; but I'm reluctant for ...
15
votes
5answers
2k views

How to make a GIS inventory?

My office will be seeing a big change in its GIS section. This section has been operational since the 1980's and has a huge collection of GIS data (i.e., shapefiles, raster files, data, etc) but never ...
5
votes
3answers
2k views

Python, comtypes and ArcObjects: Error creating AppROT object

I am experimenting with comtypes and ArcObjects under Python 2.6.5 and ArcGIS 10 SP1. I'm using the pure Python method to wrap the ArcObjects OLBs described in this answer, but getting an error in the ...
9
votes
2answers
3k views

Cartographic techniques for symbolizing routing data

Some common problems with displaying routes created from street data, such as bus routes, include: Routes may overlap themselves, such as when a route takes the same road in opposite directions ...
4
votes
2answers
568 views

Does Calculate Value (Model Only Tool) work correctly in tools run in Batch?

Am I correct that if my model has a model-only tool (Calculate Value), and then I run the model as a batched process, it will not run the Calculate Value expression? I wrote a model to upload, ...
11
votes
5answers
8k views

How to perform Raster Reclassification in QGIS?

Is there a way to do reclassify a raster image to Qgis? In Arcgis you can do that in Spatial analyst Tools→Reclass→Reclassify Any ideas?
9
votes
5answers
9k views

Can QGIS read an ODBC connection?

I have a co-worker who manages a large MS Access database that contains X & Y fields for various locations he tracks. We have previously exported the data to CSV and used the QGIS Delimited Text ...
7
votes
2answers
2k views

QGIS display world country shape files centered on pacific ocean using Robinson, Miller Cylindrical or other projection

I wish to display a map in QGIS (world country shapefiles) showing all countries but centered on the Pacific area. I am not familiar with Proj4, so is there any way this can be done in QGIS please?
5
votes
6answers
5k views

How to georeference a dxf?

I have got myself a dxf which is built with units in the wrong scale. How do I upscale that in QGIS? Note it does open in QGIS, just in the wrong map units and location.
4
votes
4answers
6k views

Problems with OpenLayers and WFS - proxy.cgi issues

I am having problems getting WFS data to display on a map using OpenLayers/GeoExt/GeoServer. I created a proxy script like on this page: ...
47
votes
4answers
13k views

Spatial clustering with PostGIS

I'm looking for spatial clustering algorithm for using it within PostGIS-enabled database for point features. I'm going to write plpgsql function that takes distance between points within the same ...
28
votes
4answers
4k views

Curved point-to-point “route maps”

I have recently been looking at airlines web pages that display their routes departing a certain city to all other cities they service. I would like to be able to create similar curved routes between ...
14
votes
9answers
18k views

How to convert KML to shapefile without losing attributes?

I'm new to QGIS and all geoinformation itself but have to work on some difficult stuff. I have a KML file with hundreds of points. To each point there is information, such as Name, Power, Age (it's a ...
23
votes
2answers
2k views

How to represent trend over time?

I have a time series of rasters where the cells of each raster represents some value at a certain time. I'd like to generate a map that highlights the magnitude of positive or negative trends in this ...
16
votes
10answers
4k views

Getting started with Arcobjects

What is the best route or place to get started with arcobjects if one is not a developer and not aiming to become a developer? I've been using gis professionally for a long time, almost two decades, ...
35
votes
4answers
7k views

What are the pros and cons of PostGIS geography and geometry types?

My company uses geometry (the_geom) data type for storing geospatial data. I've recently been acquainted to the concept of geography (the_geog) data type which, as I understand it, stores the SRID ...
21
votes
2answers
28k views

How to calculate polygon areas in QGIS?

Hi I would like to simply calculate areas of a area-shape file in square meters or in acres (ha). I didn't find that functionality in the vector tools. Could anyone here help me with that?
14
votes
9answers
26k views

How to import a DWG into a QGIS project?

I have a lot of DWG files like base map, and water and wastewater network. I am lookin for the principal steps to import my files into my QGIS project.
8
votes
5answers
3k views

How to create points in a specified distance along the line in QGIS?

I want to use QGIS creating points along the line, but in specified distance. I found two GRASS tools in SEXTANTE Toolbox: v.to.points v.segment I tried v.to.points, setting the maximum distance ...
8
votes
7answers
7k views

ogr2ogr convert all shapefiles in a directory

I have a directory with several shapefiles. How can convert all these shapefiles to MapInfo with ogr2ogr. I know how I can convert one file. And I can make a batch script writing a line for each file. ...
8
votes
6answers
5k views

How to get “.GDB” Esri File Geodatabase in QGIS for MAC OSX 10.6?

I understand there are programs like OSGeo4W that allow windows users to work with File Geodatabases, but is there something similar for Mac OSX?
8
votes
3answers
2k views

How to emulate Google Maps driving directions using pgRouting?

Would like to emulate google maps' driving directions functionality but use pgRouting instead. google's data over the project area & scale is quite a bit off so we want to use our own transport ...
4
votes
2answers
6k views

Viewing .las format LIDAR data in QGIS?

Is there an easy path to visualizing this LIDAR data? I have QGIS, and some USGS LIDAR data in (.las) format downloaded from http://lidar.cr.usgs.gov/ . This means I have both the (.las) and ...
4
votes
1answer
5k views

Elseif Conditional Statement in QGIS Field Calculator

I am trying to write an ELSEIF conditional statement in QGIS Field Calculator (version 1.8.0). I have used an example I found online: CASE WHEN val < 0 THEN 'negative' WHEN val = 0 THEN ...
2
votes
2answers
1k views

Iterate through multiple Raster files and compute statistics using Zonal Statistics

I have a large number of raster images. What I'd like to do is to compute statistics on different sections of these raster files using a polygon. I think everyone is suggesting Zonal statistics. ...
48
votes
20answers
14k views

What are some Free and Open Source GIS Desktop packages

Can someone please give me a list of free and open source GIS desktop packages?
30
votes
5answers
11k views

Comparison of the different open source GIS servers

I currently know the following open source GIS servers: Geoserver: java based, vector and bitmap support, also supports. Is now on par with mapserver (performance-wise). mapserver: c/c++, used to be ...
40
votes
10answers
13k views

Creating drive time polygons using open source tools

Is anyone using open source tools and/or data to generate drive time polygons that radiate out from a given location? For example, I have used ESRI products like Network Analyst and Business Analyst ...
23
votes
9answers
5k views

Seeking options for Spatial ETL (Extract, Transform, Load)?

I am interested in the pro's and con's of various spatial ETL (extract, transform, load) tools. If you have used the items listed here (or add your own), please share your opinions and experiences. ...
23
votes
9answers
6k views

What are useful websites for scouting GIS related jobs?

What are useful websites for scouting GIS related jobs?
30
votes
8answers
4k views

Representation of network flows

This is a sample transportation network flow I've done a year ago based on 26 zones. For a project I'm working on now, I need to represent the flows over 1,000 zones with directionality. Any ...
18
votes
6answers
10k views

How to convert image of map into vector format?

What is the best way of converting a gif of a map into a vector format, such as a shapefile? The only relevant parts that I am interested in are the outline of the island so I realize some manual ...
43
votes
7answers
11k views

What are Esri's new “ArcGIS for Professionals” and “ArcGIS Pro”?

After looking through all the stuff that was released or talked about at the Esri UC I am still genuinely confused by what ArcGIS for Professionals is. I will admit that it looks pretty cool, and has ...
26
votes
4answers
2k views

How to use directional shading on boundaries for cartographic effect?

The attached screenshot of a National Geographic map shows some beautiful directional shading of boundaries. I'm trying to reproduce this sort of shading for a burn perimeter map, as I want to ...
23
votes
2answers
10k views

How to change the SRID of exisisting data in PostGIS?

While importing my shapefile data to PostGIS, I did not select the proper Projection. How do I now change the SRID of the data, without transforming the Coordinates?
22
votes
1answer
8k views

Trilateration algorithm for n amount of points

I need to find algorithm that can calculate centroid A (aka gravity center, geometric center, center of mass) from the figure where circles T1,T2,T3,T4,T5,..,Tn intersect AND length of line R from ...

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