/usr/share/psychtoolbox-3/PsychGamma/FitGammaSigFun.m is in psychtoolbox-3-common 3.0.11.20140816.dfsg1-1.
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1 2 3 4 5 6 7 8 | function [err,con] = FitGammaSigFun(x,values,measurements)
% [err,con] = FitGammaSigFun(x,values,measurements)
%
% Error function for sigmoid function fit.
predict = ComputeGammaSig(x,values);
err = ComputeRMSE(measurements,predict);
con = [-x(1) -x(2) -x(3)];
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