Perceptually improved colormaps

7 perceptual colormaps with rainbow-like colors and 1 with heat colors

PMKMP Returns perceptually balanced colormaps
PMKMP(N,SCHEME) returns an Nx3 colormap.
usage: map=pmkmp(n,scheme);
%% Example1: 128-color rainbow with cubic-law luminance (default)
load mandrill;
imagesc(X);
colormap(pmkmp(128));
colorbar;
%% Example2: 128-color palette for azimuthal data
a=0:8:360;
b = repmat(a,[46 1]);
imagesc(b);
colormap(pmkmp(128,'IsoAZ'));
colorbar;
JUSTIFICATION: rainbow, or spectrum color schemes are considered a poor choice for scientific data display by many in the scientific community (see for example reference 1 and 2 in the help) in that they introduce artefacts that mislead the viewer. "The rainbow color map appears as if it is separated into bands of almost constant hue, with sharp transitions between hues. Viewers perceive these sharp transitions as sharp transitions in the data, even when this is not the casein how regularly spaced (interval) data are displayed (quoted from reference 1). This submission is intended to share the results of my efforts to create more perceptually balanced color maps. Please see output arguments section for descriptions.
See files examples.m, examples1.m, and example2.m and associated figures for more examples
See files MakeLabPlotUsingColorspace.m and CompareLabPlotsUsingColorspace.m for some demonstrations.
See also: JET, HSV, GRAY, HOT, COOL, BONE, COPPER, PINK, FLAG, PRISM, COLORMAP, RGBPLOT

Extensive reference list and list of other FEX submissions of interest included in the help
Please visit my blog to read about the background research:
http://mycarta.wordpress.com/2012/05/29/the-rainbow-is-dead-long-live-the-rainbow-series-outline/

Author: Matteo Niccoli
e-mail address: [e-mail]
Release: 4.04
Release date: November 2014