Hands on lunch (30-4-2018, Deltares, Delft) by Willem Ottevanger and Marc Weeber
GRASS is deliverd with QGIS.
This is the easiest option to get started. Choose the QGIS Standalone Installer Version 2.18 (64 bit).
Before starting we need to setup the GRASS projection and mapset. In the scripts folder you will find the following command:
> setup_grass_location.bat
This will bring up the following window. Click 'New' to create a new GRASS location
Fill in Project Location as: RD_new and the GRASS Mapset to Amersfoort / RD New
Select a method to choose the EPSG code:
We will use Amersfoort / RD new
including the datum transformation
A summary is provided of the newly defined location
A new mapset can be created by using the 'New' button. Call this mapset 'mapset1'
After this you can press 'Quit'.
-
Load a command window with the necessary paths loaded for GRASS
> cmd_grass.bat -
Run the following command within the command window to check your setup
> %GRASS_PYTHON% setup_grass_environment.py
After running you should see the following output:
Current GRASS GIS 7 environment:
{u'MAPSET': u'mapset1', u'GISDBASE': u'D:\\user\\Documents/grassdata', u'LOCATION_NAME': u'RD_new'}
Available raster maps:
Available vector maps:
Instead of using the python environment, it is also possible to connect to the grass python libraries from a locally setup python environment using Anaconda. This has advantages of interactive code development, as well as interfacing with other python libraries which can be installed using conda (or otherwise pip).
- Start an Anaconda prompt (from Start menu)
- Install a clean anaconda environment with jupyter
> conda create -n gispy python=2 jupyter
- Activate the conda enviroment
> activate gispy
- In a later phase you can run start the environment using from the scripts folder
> start_conda_cmd.cmd
- Nexy set all relevant paths
> set_conda_grass_env.bat
- In the exercises folder run
> jupyter notebook ex1.ipynb
GRASS commands are preceded by the following prefixes depending on the functionality:
| prefix | section | description |
|---|---|---|
g. |
general |
generic commands |
v. |
vector |
2D/3D vector data processing |
r. |
raster |
2D raster data processing |
db. |
database |
attribute data management |
d. |
display |
display commands |
i. |
imagery |
imagery data processing |
ps. |
postscript |
map outputs |
r3. |
raster3D |
3D raster data processing |