SearchGammaTable

>Psychtoolbox>PsychCal

values = SearchGammaTable(targets, input, table)

Return the [0-1] entry from the passed table that produces
output closest to the [0-1] target.

The targets are assumed to be a row vector.
The table is assumed to be a column vector.
The returned indices and values are are row vectors.

Works by using Matlab’s interp1, with the output as the x values and
the input as the f(x) values.

I suspect that this is a fast Matlab implementation, but those who want
to try are welcome to try to do better. (Remember, though, that this
routine gains in efficiency the more searches are done at once.
This is because it contains no dreaded loops.)

4/2/94 dhb Added code that checks for special case of zero output.
4/4/94 dhb Fixed code added on 4/2.
4/5/94 jms Fixed code added on 4/2.
1/21/95 dhb Write search as a loop. Loses time and elegance,
but prevents allocation of arrays that may be huge.
11/16/06 dhb Renamed as SearchGammaTable.
dhb Start work on converting to [0-1] universe. Change
name and interface.
11/20/06 dhb Finish update by calling through MATLAB’s interpolation function.
9/15/08 dhb Handle case where there are a bunch of zeros at the beginning of gamma table.
5/26/12 dhb Improve comment. This was not doing exhaustive search.

Path   Retrieve current version from GitHub | View changelog
Psychtoolbox/PsychCal/SearchGammaTable.m