function rf=lpcla2rf(la)
%LPCLA2RF Convert log areas to reflection coefficients RF=(LA)


%      Copyright (C) Mike Brookes 1997
%
%      Last modified Tue May 12 16:08:57 1998
%
%   VOICEBOX home page: http://www.ee.ic.ac.uk/hp/staff/dmb/voicebox/voicebox.html
%
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%   This program is free software; you can redistribute it and/or modify
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[nf,p2]=size(la);
rf=-tanh((la(:,1:p2-1)-la(:,2:p2))/2);