Mapping Hacks

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Chapter 6, Mapping on Your Desktop

#69 Find Your Way Around GRASS

HACK

The GDAL and OGR utilities can take a little getting used to, but they make

a lot of things possible and even easy that would have been difficult or

impossible otherwise. What’s more, many an open source GIS application

depends on the GDAL and OGR libraries for GIS data handling.

HACK

#69

Find Your Way Around GRASS Hack #69

The full power of GIS can be a little overwhelming at first, but a little patience

and a little practice is all it takes to make GRASS do your bidding.

GRASS is a powerful and free set of tools for analyzing and presenting geo-

graphic data. For details on how to install GRASS, see http://mappinghacks.

com/GRASS/. Once you’ve done that, it’s time to download the global sam-

ple data set and try out some basic tasks to get a feel for how GRASS works.

First, make a directory somewhere on your system in which to store your

GRASS data, which can be anywhere convenient that you have write access

to (I put mine in /home/sderle/gis/grass). Then download the sample global

data set from http://grass.itc.it/sampledata/global_grass5data.tar.gz. Unpack

the tar file inside your GRASS data directory:

$ cd ~/grass # or wherever you put it

$ tar xvfz ~/global_grass5data.tar.gz

You should see a bunch of files unpack into that directory. Now, start up

the GRASS 5 shell by executing

grass5 at your shell prompt. You’ll be taken ...