on February 14, 2023
Segmentation Fault (segfault) when using OGR CreateField() in Python
Geographic Information SystemsHow do I fix a segmentation fault in Python? You can trace it in following ways. Add sys. settrace at the very first line of the code. Use gdb as described by Mark in this answer.. At the command prompt gdb python (gdb) run /path/to/script.py ## wait for segfault ## (gdb) backtrace ## stack trace
on February 14, 2023
Concatenate geospatial pdfs
Geographic Information SystemsHow do I combine multiple PDFs into one PDF? Open Acrobat to combine files: Open the Tools tab and select “Combine files.” Add files: Click “Add Files” and select the files you want to include in your PDF. You can merge PDFs or a mix of PDF documents and other files. How do I add
on February 14, 2023
Are US Census tracts GEOID the same across different years?
Geographic Information SystemsIs geoid the same as FIPS? The full GEOID for many levels of geography combines both the FIPS codes and Census Bureau codes. For example, census tracts, block groups and census blocks nest within state and county; therefore, the GEOIDs for each of these geographic areas contains both the state and county FIPS codes, in
on February 14, 2023
Using ArcGIS Feature Compare in ArcPy?
Geographic Information SystemsWhat is the difference between feature class and feature layer in ArcPy? The feature class contains geographic features, such as buildings, parcels, cities, roads, and earthquake epicenters, and attribute information about the features. The feature layer is a part of the map or scene, and the map or scene is stored in the project. How
on February 14, 2023
OpenLayers transform EPSG 27700 coordinate to Google 900913
Geographic Information SystemsWhat projection is 900913? Answer. 900913 is used as a well-known ID (WKID) by some Web services for the spherical Mercator-based coordinate system used by Bing maps and Google maps. The 900913 value is a representation of the Google name and originated in the blog entry, Google Projection: 900913. How do I get XYZ coordinates
on February 14, 2023
Downloading contextual GIS layer using QGIS
Geographic Information SystemsHow do I import a layer into QGIS? Open QGIS and click LAYER > ADD LAYER > ADD VECTOR LAYER. Select the zipped shapefile. Click OPEN. You have now successfully imported a shapefile into QGIS. How do I open a .DB file in QGIS? Selecting a file from the list and clicking [Open] loads it
on February 14, 2023
Is it possible to pass multiple WMS layer to a processing script
Geographic Information SystemsHow to convert a WMS file to a shapefile? WMS. Shapefiles can be exported through the right-click menu and through the File menu. Select the item in the Project Explorer, then File | Save As to bring up the Save As dialog. In this dialog you can change the “Save as type” to “Shapefile (*.
on February 14, 2023
Get total feature count in WFS service
Geographic Information SystemsWhat is the maximum number of features in GeoServer WFS? A WFS request can potentially contain a large dataset that is impractical to download to a client, and/or too large for a client’s renderer. Maximum feature limits are also available for feature types. The default number is 1000000. What is feature ID in WFS? The
on February 14, 2023
How to merge polygons not sharing same boundaries based on attribute with one expression in qgis
Geographic Information SystemsHow do I merge polygon boundaries in Qgis? Click on the “Select Single Feature” button. While pressing Ctrl-key select the enclave and the surrounding polygon. Click on the “Merge Selected Features” button. How do I merge polygons with the same attribute in Qgis? Process Click on the Vector menu, Data Management tools, Merge Shapefiles to
on February 14, 2023
Display GeoTIFF image in OpenLayers 6
Geographic Information SystemsHow do I view GeoTIFF? You can download QGIS from their website here. Open QGIS and start with a new project. Next, click on the Layer menu => Add Raster Layer. Select your GeoTIFF file and click “add”. Your orthomosaic will now be visible. How do I view a TIF file in Qgis? Open QGIS