CMSCOPE changed

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diff --git a/modules/cacsd/macros/bstap.sci b/modules/cacsd/macros/bstap.sci
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+// Scilab ( http://www.scilab.org/ ) - This file is part of Scilab
+// Copyright (C) INRIA -
+//
+// This file must be used under the terms of the CeCILL.
+// This source file is licensed as described in the file COPYING, which
+// you should have received as part of this distribution.  The terms
+// are also available at
+// http://www.cecill.info/licences/Licence_CeCILL_V2.1-en.txt
+
+
+function [Q]=bstap(sl)
+    // Best approximant Q of Sl
+    //      ||Sl-Q||    =  ||Tsl||
+    //              inf
+    // ||Tsl|| norm of hankel operator
+    //-- sl is assumed antistable
+    //-- Q : best stable approximation of Sl
+    //!
+    //balancing
+    //-----------------------------------
+
+    slt=gtild(sl);slt=balreal(slt);sl=gtild(slt),
+    // D such that DB1'+sC1 = 0 , DD' = s**2I
+    //-------------------------------------------------
+    [a,b,c]=sl(2:4),[n,n]=size(a),[m,n]=size(c),
+    x=-obs_gram(sl),s=x(1,1),
+    [w,r]=rowcomp(x-s*eye()),r=n-r,
+    b1=b(1:r,:),c1=c(:,1:r),
+    [u1,s1,v1]=svd(-c1'),[u2,s2,v2]=svd(b1),
+    v2=v2(:,1:m),dd=s*v1*v2',
+    //
+    //--------------------------------
+    a22=a(r+1:n,r+1:n),
+    b2=b(r+1:n,:),c2=c(:,r+1:n),
+    sig=x(r+1:n,r+1:n),
+    bb=-inv(s**2*eye()-sig*sig)*(sig*b2+s*c2'*dd),
+    aa=-(a22+b2*bb')',cc=c2*sig+dd*b2',
+    Q=syslin("c",aa,bb,cc,dd),
+endfunction