[dkl] =
ConeIncToDKL(coneInc,bg)
Convert from incremental cone coordinates to DKL
coordinates.
The code follows that published by Brainard
as an appendix to Human Color Vision by Kaiser
and Boynton.
8/30/96 dhb Converted this from script.
Psychtoolbox/PsychColorimetric/ConeIncToDKL.m