Creates a broad range color map that looks good in color as well as when reduced to grayscale for low cost publication.
Finished colormap encodes small values with a bluish color, intermediate values in green to orange, and large values with a redish/salmon color. The greyscale is linear.
What about adding a next optional parameter which would set the "darkness/lightness", such that the mapping between color and grayscale wouldn't be linear.
Easy way how to do is to add a line, e.g.
RGBmap = brighten(RGBmap,0.2)
The problem is, however, that the mapping is not smooth (as can be seen on the plot, if I do e.g. colorGray(100,1)).
I wrote something like this (independently) myself. However, it is full greyscale (i.e. black to white) and has a wider gamut of colours. It is available as the 'contrast' colourmap of the SC package (id 16233), which also has other "colour to gray" colourmaps too: 'earth', 'pinker', 'pastel'.
23 Sep 2008
Manuel Guizar
The code works well but it does not use the entire gray scale range.
16 Jan 2008
Garret B
Alex is my hero!
19 Aug 2007
Will Robertson
Great for large numbers of levels, but quite poor for just a few (e.g., if you're labelling three or four lines on a plot). In fact, the code breaks for numberOfLevels < 3. But I don't believe that's the goal of the package, so that's okay.
07 Dec 2006
Evan Variano
Colormap that unites grayscale and full color - hooray! - Where have you been all my life?!
Updates
17 Nov 2006
input 'numberOfLevels' is now optional. Optimized for speed and readability by vectorizing code. Added the debug plotting options.
Thx to PederAxensten for suggestions and significant code snippet.