GDAL & OGR (Importance & Installation)

GDAL & OGR libraries allow you to perform various GIS operations like, Flow Direction or working with DEM few raster & vector analysis outside GIS environment.

Image by Gerd Altmann from Pixabay

What Knowledge one should have : Basic Programming, Python

What software you need : Python IDLE or command line, GDAL libraries files (explained later)
Installation :
1- Once you have Python installed.

2- Start python IDLE to check which version of python you are using available at top as shown

Python IDLE

3- Install two files available at link below based on your version of python.

Download Link: http://www.gisinternals.com/query.html?content=filelist&file=release-1500-gdal-2-1-2-mapserver-7-0-2.zip

Install first : gdal-201-1500-core.msi and then: GDAL-2.1.2.win32-py2.7.msi

* Note specify the path C:\Python27\ArcGIS10.3\Lib\site-packages\ for GDAL-2.1.2.win32-py3.2.msi as shown in figure for (ArcGIS lib installed in python)

Python Installation

4- Setting Environment Variables

Go to control Panel type Env in search tab as shown in screen, select EDIT system environment variables,

(as shown)

Setting Environment Variables

Go to Advance-> Environment Variables, Select path from System Variables and paste (as shown) ;C:\Program Files (x86)\GDAL Note ; is must

System Properties

Add two new system variables

Variable name: GDAL_DATA
Variable value: C:\Program Files(x86)\GDAL\gdal-data

GDAL DATA Adding

Variable name: gdalplugins

Variable value: C:\Program Files(x86)\GDAL\gdalplugins

Edit System Variables

To check installation is correct start command line type gdalinfo --version (2 spaces after gdal), it will give you result. it will give you version and release date, next start idle and type import gdal press enter if it runs fine, if it gives an error cut and paste file on desktop ogr_MSSQLSpatial.dll (C:\Program Files (x86)\GDAL\gdalplugins). Hope it works now.

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