>Psychtoolbox>PsychColorimetricData

absorbance = ShiftPhotopigmentAbsorbance(S,absorbance,lambdaMaxShift,shiftMode)

Function to shift photopigment absorbances. Probably a reasonable
approximation to biological reality for small shifts of lambda max.

There are two ways of shifting photopigment absorbances:
‘linear’ - default
Shifts the photopigment absorbance on a linear wavelength axis. This
is what Asano, Fairchild, & Bonde (2016), PLOS One, doi:
10.1371/journal.pone.0145671 do.

‘log’
Shift the photopigment absorbance along a log wavelength axis to give it
a new lambda max. This is the way Lamb (1995) suggested would lead to a
close approximation of biological shifts in photopigment lambda-max.

Linearly extrapolates as necessary to preserve wavelength sampling of
input.

2/8/16 dhb, ms Wrote it.
2/10/16 dhb, ms Do shifting on a fine (0.25 nm) wavelength spacing.
2/12/16 ms Implement linear and log shifting.