[R] Log color scale

Kartik Pappu kartik.pappu at gmail.com
Sun Jul 30 04:16:22 CEST 2006


Hi all,

In response to a previous post about plotting a numeric square matrix
as a colored matrix, I was referred to both image and the
color2D.matplot function in the plotrix package.  Both have worked for
me thanks!!

However I need to plot my data in a log transformed color scale.  Is
this possible?  I will be happy to explain further, but basically I
need to do this because there are large variations in the max and min
values of my raw data and I am trying to highlight the differences in
the values at the lower end of my raw data (while still displaying the
values at the high end of the spectrum for comparison) so if figured
the best way to represent this on a (RGB) color scale is to do it with
a log transform.  I do not want to use too many colors because that
make the figure too busy.

Any suggestions on how to achieve this.

Kartik



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