vlt.neuro.vision.contrast.indexes.contrastfit2c50

  CONTRASTFIT2C50- Compute Half maximum

    C50 = vlt.neuro.vision.contrast.indexes.contrastfit2c50(CONTRAST, RESPONSE)

   Given contrast in 1 percent steps in CONTRAST, this function
   computes the half maximum value that is defined as:

   value of C such that R(C50) = 0.5 * max(R)

   Units of contrast can be percent or from 0 to 1.

   See Heimel et al. 2005 (Journal of Neurophysiology)