cbrewer2

Cynthia Brewer's ColorBrewer palettes, ported to MATLAB, with nice interpolation.

This package makes Cynthia Brewer's ColorBrewer schemes available in MATLAB, with a user-friendly interface.
The schemes can be interpolated to include more colours. By default, this is done using cubic interpolation in the almost perceptually uniform CIELAB colour space to prevent inflection points arising and distorting the scheme.

--- Requirements ---
To interpolate the colour schemes in CIELAB space, the FEX package COLORSPACE is required.
https://www.mathworks.com/matlabcentral/fileexchange/28790-colorspace-transformations
If you don't have a copy available, CBREWER2 will automatically prompt you to download it.

--- Features ---
* Supports all ColorBrewer 2.0 colour schemes.
* Has a simple interface, requiring just the colour scheme name and (optionally) number of colours to be specified.
* Can also accept a (redundant) type input, making the input format also compatible with that of CBREWER, so CBREWER2 serves as a drop-in replacement.
* Default number of colours is the same as the current colormap.
* Outputs a MATLAB standard N-by-3 numeric RGB array.
* Interpolates up to colormaps larger than the available colour scheme using a perceptually uniform colour space to prevent artefacts caused by interpolation in RGB space.
* Cyclically repeats qualitative colour schemes if more colours are requested than are available, mimicking the behaviour of the built-in LINES and FLAG qualitative colour maps.
* Is fully compliant with ColorBrewer's Apache license conditions.
* However it is NOT compatible with a minority of MATLAB functions which require a colormap to be provided as a string (eg: CONTOURCMAP). If you need this, please consult BREWERMAP (FEX: 45208) as a viable alternative.

There are several other ColorBrewer implementations available on MATLAB File Exchange, with some overlap between their feature sets. However none of the others have all the features which CBREWER2 possesses. In particular the perceptually uniform interpolation is important if you need more than 12 colours in your colormap.

--- Notes ---
This product includes color specifications and designs developed by Cynthia Brewer (http://colorbrewer.org/). See the ColorBrewer website for further information about each colorscheme, colorblind suitability, licensing, and citations.

You can report bugs and suggest new features on GitHub:
https://github.com/scottclowe/cbrewer2