Country Data Processing

This tutorial describes how to

• find free data of country on Internet
• create new GRASS location
• import found data into GRASS
• create new vector layers from existing data
• create labels
• display map of a country

GRASS Installation

Required elements

• GRASS GIS system installed
• download SPEARFISH data http://grass.itc.it/sampledata/spearfish_grass60data-0.3.tar.gz

Create directory structure required for this tutorial

• dataset directory

  $ mkdir ~/grass

• input data directory

  $ mkdir ~/grass/indata

Create GRASS location using SPEARFISH data to be able create new locations

  $ cd ~/grass
  $ tar zxf spearfish_grass60data-0.3.tar.gz

Start GRASS

  $ grass -text spearfish60/PERMANENT

Obtaining Data

We assume that one wants to create UK map. Following steps can be easily applied to other countries' data.

Country related GIS data can be obtained from Digital Chart of the World.

First create country related input directory

  $ mkdir ~/grass/indata/uk

Let's download UK data

• go to Digital Chart of the World
• click Europe link
• choose United Kingdom in select box on the right and click Continue
• page _Digital Chart of the World Layer Interface for United Kingdom_ will be displayed
• click Download Data button
• another page will be shown, mark checkboxes
  • Populated Places (Polygon)
  • Roads (Line)
  • Rail Roads (Line)
• click Continue
• on new page click Compute Data
• on new page you will be able to obtain set of data, i.e.

  <NUMBER>.tar.Z

 where <NUMBER> is your filename with data exported by DCW

• do not hesistate to download data and put it to to ~/grass/indata/uk directory