RuG/L04

Manuals

maprgb

Description

draw a colour map, for example, using the data from 3D multidimensional scaling

the result is an Encapsulated PostScript image

Synopsis

maprgb [-e] [-r] [-o filename] configfile vectorfile

Options

-e
equivalent scaling of colour axes
-r
raw input, no scaling of colour axes
-o filename
output file

Purpose

This programs draws a map, giving each location (set off by triangulation from other locations) a separate colour. The colours are set in a vectorfile which must have vectors of size 3 (for instance, created by running the program mds in 3 dimensions). The values in the vectorfile are used as red, green, and blue colour components. The components can have any values: each component will be scaled onto the maximum range of permissible colour values.

See Map configuration file for the syntax of the configfile.

Equivalent scaling of colour axes

By default, all three vector dimensions are scaled separately to map onto the full range of its colour component, even if the range of values in one vector dimension is much smaller than in another dimension.

The option -e changes this behaviour. The same scaling is applied to each vector dimension. Usually, two out of three dimension will map onto a smaller part of the range of its colour component. In other words, there will be less colour separation in two out of three colour components.

Raw input, no scaling of colour axes

With the option -r, no scaling on the vector dimensions is done. All input values must be in the range from zero to one.