vlt.neuro.vision.contrast.indexes.contrastfit2relativemaximumgain
  CONTRASTFIT2RELATIVEMAXIMUMGAIN - Compute relative maximum gain
    [RMG,CVALUE] = vlt.neuro.vision.contrast.indexes.contrastfit2relativemaximumgain(CONTRAST, RESPONSE)
   Given contrast in 1 percent steps in CONTRAST, this function
   computes the relative maximum gain that is defined as:
   max(dR/dC)
   Units of contrast can be percent or from 0 to 1.  If they are percent
   these units will be converted to 0-1, so that the units of dC are 
   in fractions.
   CVALUE is the contrast value where the maximum occurs.
   See Heimel et al. 2005 (J Neurophysiology)