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1500 questions
19
votes
4 answers

Opening ESRI Personal GeoDatabase (*.mdb) in QGIS

How can I open an ESRI Personal Geodatabase (*.mdb; ArcGIS 10.2) in QGIS 2.6 or above?
David
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19
votes
7 answers

Fastest way to spatially join a point CSV with a polygon Shapefile

I have a 1 billion point CSV file and a shapefile with around 5,000 polygons. What would be the fastest way to spatially join points and polygons? For each point, I need to get the containing polygon id. (Polygons don't overlap.) Usually, I'd load…
underdark
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19
votes
5 answers

Concatenating fields in field calculator of QGIS?

Is there a way to concatenate fields in field calculator of QGIS? (e.g. hectares + ' ha')
vascobnunes
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19
votes
2 answers

Reading postgis geometry with shapely

I am doing a small-scale workflow in ipython notebook with geopandas and shapely, pulling a bunch of geospatial data, sometimes from shapefiles, sometimes from postgis (where more expensive processing is performed). Now, I then pull the postgis…
ako
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19
votes
4 answers

Creating one-sided buffers or parallel lines in PostGIS?

I'm looking for a way to create so-called one-sided buffers or parallel lines in PostGIS. Example: 1. buffer, 2. one-side, 3. both-sides I've found some discussion on the mailing list from 2009 and information that it has been implemented in GEOS,…
underdark
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19
votes
1 answer

Calculating Focal Statistics for Special Neighborhood?

I'm looking to calculate focal statistics for each cell of a raster, within a neighborhood of a specified criteria. Background - I have three binary rasters, each representing a single vegetation type of interest. I'd like to calculate the percent…
CSB
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19
votes
5 answers

Converting osm file to shapefile (or data frame) in R

I was looking for a road shapefile for Australia today. I ended up going to Geofabrik. Open Street Map has data in .osm format. But they do not have one in .shp for Australia. If possible, I want to convert the osm files to shapefiles using R. I…
jazzurro
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19
votes
5 answers

Are there PhD programs that specifically focus on GIS, and if so, what is the typical outcome?

I know of the University of Pittsburgh where you can get a PhD in information science that focuses on Geoinformatics, which seems kind of cool. I've been looking around but it seems that most PhD programs in Geography focus on either human or…
Josh Klein
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19
votes
3 answers

Change OpenLayers 3 view center

I'm using OpenLayers 3 to interact with some maps. I first declare my map: map = new ol.Map({ target: 'map', layers: [ new ol.layer.Tile({ source: new ol.source.OSM() }) …
Guillelon
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19
votes
2 answers

How is the data access cursor performance so enhanced compared to previous versions?

The data access module was introduced with ArcGIS version 10.1. ESRI describes the data access module as follows (source): The data access module, arcpy.da, is a Python module for working with data. It allows control of the edit session, edit…
Aaron
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19
votes
2 answers

Is it possible to use comments in QGIS Query Builder with ESRI shapefiles?

I am trying different queries in the Query Builder. Is there a way to comment the query? I tried with /* */ # -- without success : An error occurred when executing the query. The data provider said: OGR[3] error 1: SQL Expression Parsing…
nebi
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19
votes
8 answers

How to Geocode a Google Sheet?

I have a spreadsheet in Google Sheets with about 20-30 rows, with the following 6 columns: ID Name Address Cell_No Latitude Longitude where the last two columns are empty. What is an easy way, for a novice user who is a non-programmer, to…
Devdatta Tengshe
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19
votes
5 answers

Seeking shapefile of city boundaries in US?

Where can I find a shapefile that contains boundaries for the major cities in the United States? I have tried the census website but could not find anything.
Furlong
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18
votes
3 answers

Leaflet rendering TileMill tiles in the wrong order

I'm stumped, and quite a lot of searching has turned up nothing helpful. I'm on the first step of what will ultimately be a map with three raster layers and three layers of markers (with controls to toggle between the rasters and their associated…
Dani
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18
votes
3 answers

Join CSV file to shapefile using gdal/ogr

I have a shapefile with several attributes, for example "YEAR", "COUNTY", and "AREA". I also have a CSV file with more fields that I want in the shapefile, such as "POPULATION". Both the shapefile and the CSV file have a field "GISJOIN". I know how…
Lincoln Mullen
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