/usr/share/psychtoolbox-3/Psychometric/FindThreshWeibYN.m is in psychtoolbox-3-common 3.0.9+svn2579.dfsg1-1.
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1 2 3 4 5 6 7 8 9 10 11 12 13 14 | function threshold = FindThreshWeibYN(pyes, alpha, beta)
% threshold = FindThreshWeibYN(pcorrect, alpha, beta)
%
% Invert Weibull function to find threshold
% for given pcorrect, alpha, and beta.
% This function should invert ComputeWeibullYN().
%
% threshold = alpha * pow( -1.0*log(1.0-pyes) , 1.0/beta );
if (pyes>=0.0 & pyes<1.0)
% ASSERTEND(pyes>=0.0 & pyes<1.0);
end
threshold = alpha .* ( -1.0 .* log(1.0-pyes)).^(1.0./beta);
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