1 files changed, 23 insertions, 0 deletions
diff --git a/modules/cacsd/macros/zeropen.sci b/modules/cacsd/macros/zeropen.sci
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+++ b/modules/cacsd/macros/zeropen.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 [Z,U]=zeropen(Sl)
+    //Z = sE - F = zero pencil of Sl=[A,B,C,D]
+    // With U row compression of [B;D] i.e, U*[B;D]=[0;*];
+    //U*[-sI+A |B;   [ Z |0;
+    //      C  |D] = [ * |*]
+
+    s=poly(0,"s");
+    [A,B,C,D]=abcd(Sl);
+    BD=[B;D];
+    [n,m]=size(BD);
+    [U,rk]=rowcomp(BD);U=[U(rk+1:n,:);U(1:rk,:)];
+    W=U*([-s*eye()+A;C])
+    Z=W(1:n-rk,:);
+endfunction