output =
ComputeGammaPoly(x,input)
Compute gamma table using polynomial function.
Relies on Matlab's built-in polyeval.
Assumes that 1 is maximum input value
10/3/93 dhb,jms Normalize output to max of 1.
Better be sure that last value is max setting.
10/4/93 dhb Force monotonicity
6/5/10 dhb Update for [0,1] input convention.
Psychtoolbox/PsychGamma/ComputeGammaPoly.m