- function [y] = spm_phi_dot(x)
- % returns the derivative of the logistic function
- % FORMAT [y] = spm_phi_dot(x)
- % see spm_phi and spm_inv_phi
- %___________________________________________________________________________
- % Copyright (C) 2008 Wellcome Trust Centre for Neuroimaging
- % Karl Friston
- % $Id: spm_phi_dot.m 1143 2008-02-07 19:33:33Z spm $
- % apply
- %--------------------------------------------------------------------------
- u = exp(-x);
- y = 1./(1+u).^2.*u;
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