This function requires the rgb function found here: http://www.mathworks.com/matlabcentral/fileexchange/46872
The rgb function uses a database which was created by showing hundreds of thousands of viewers more than 900 of the most commonly-used colors on the internet, and getting users to use their own words to describe that color. The result is a database of the most commonly-used names for colors, the way they are perceived on computer monitors.
The rgbmap function presented here creates color maps using any number of these strings as inputs.

SYNTAX
cmap = rgbmap('first color name','second color name')
cmap = rgbmap('first color name','second color name',...,'nth color name')
cmap = rgbmap(...,levels)
rgbmap(...)

DESCRIPTION
cmap = rgbmap('first color name','second color name') creates an RGB color map cmap from some first color to a second color.

cmap = rgbmap('first color name','second color name',...,'nth color name') creates a color map linearly scaled between any number of colors.

cmap = rgbmap(...,M) specifies the approximate number of levels |M| of the M x 3 output colormap.

rgbmap(...) sets the color map without creating an array in the workspace.

EXAMPLE
The example image shown above was created like this:

surf(peaks);
colorbar
rgbmap('pinkish purple','dark taupe','tiffany blue','azure','army green')