Please check the solution provided at the below link by Jason D. Yeatman which does the exact thing that you want http://web.stanford.edu/~jyeatman/AFQ/doc/utilities/vals2colormap.html#_top
function rgb = vals2colormap(vals, colormap, crange)
0002 % Take in a vector of N values and return and return a Nx3 matrix of RGB
0003 % values associated with a given colormap
0004 %
0005 % rgb = AFQ_vals2colormap(vals, [colormap = 'jet'], [crange])
0006 %
0007 % Inputs:
0008 % vals = A vector of values to map to a colormap or a cell array of
0009 % vectors of values
0010 % colormap = A matlab colormap. Examples: colormap = 'autumn';
0011 % colormap = 'jet'; colormap = 'hot';
0012 % crange = The values to map to the minimum and maximum of the colormap.
0013 % Defualts to the full range of values in vals.
0014 %
0015 % Outputs:
0016 % rgb = Nx3 matrix of rgb values mapping each value in vals to the
0017 % corresponding rgb colors. If vals is a cell array then rgb
0018 % will be a cell array of the same length
0019 %
0020 % Example:
0021 % vals = rand(1,100);
0022 % rgb = AFQ_vals2colormap(vals, 'hot');
0023 %
0024 % Copyright Jason D. Yeatman, June 2012
