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diff --git a/src/matrixOperations/spec2/dspec2a.c b/src/matrixOperations/spec2/dspec2a.c
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+/*
+ * Scilab ( http://www.scilab.org/ ) - This file is part of Scilab
+ * Copyright (C) 2008 - INRIA - Arnaud TORSET
+ *
+ * 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-en.txt
+ *
+ */
+
+
+#include "spec.h"
+#include "lapack.h"
+#include "zeros.h"
+#include "max.h"
+#include "stdio.h"
+
+
+void dspec2a(double* in, int rows,doubleComplex* eigenvalues,doubleComplex* eigenvectors){
+ int i=0, j=0, ij=0, ij1=0;
+ int symmetric=0;
+ int INFO=0;
+ int iWorkSize = 0;
+ double* pdblWork;
+ double* outReal;
+ double* outImag;
+ double* pdblLeftvectors;
+ double* pdblRightvectors;
+ double* inCopy;
+
+ inCopy = malloc((uint)(rows*rows) * sizeof(double));
+ outReal = malloc((uint)rows * sizeof(double));
+ outImag = malloc((uint)rows * sizeof(double));
+ pdblLeftvectors=NULL;
+ pdblRightvectors=NULL;
+
+
+ iWorkSize = 4*rows;
+ pdblWork = malloc((uint)iWorkSize * sizeof(double));
+
+ for(i=0;i<rows*rows;i++) inCopy[i]=in[i];
+
+
+
+ /* look if the matrix is symmetric */
+ for (i=0;i<rows;i++){
+ for (j=0;j<rows;j++)
+ if (in[i*rows+j]!=in[i+j*rows]) break;
+ if (j!=rows) break;
+
+ }
+
+ /* the matrix is symmetric if the 2 loops goes to end i.e
+ i==rows and j==rows */
+ if ((i==rows)&&(j==rows)) symmetric=1;
+
+ /* apply lapack function according to symmetry */
+ if(symmetric){
+ C2F(dsyev)( "V", "U", &rows, inCopy, &rows, outReal, pdblWork, &iWorkSize, &INFO );
+ for (i=0;i<rows*rows;i++) eigenvectors[i]=DoubleComplex(inCopy[i],0);
+ dzerosa(outImag,1,rows);
+ }
+ else {
+ pdblRightvectors=malloc((uint)(rows*rows) * sizeof(double));
+ C2F(dgeev)( "N", "V", &rows, inCopy, &rows, outReal, outImag,
+ pdblLeftvectors, &rows, pdblRightvectors, &rows, pdblWork, &iWorkSize, &INFO );
+
+ for(j = 0 ; j < rows ; j+=2){
+ for(i = 0 ; i < rows ; i++)
+ {
+ ij = i + j * rows;
+ ij1 = i + (j + 1) * rows;
+ eigenvectors[ij] = DoubleComplex(pdblRightvectors[ij],pdblRightvectors[ij1]);
+ eigenvectors[ij1] = DoubleComplex(pdblRightvectors[ij],-pdblRightvectors[ij1]);
+ }
+ }
+
+ }
+
+
+ zzerosa(eigenvalues,1,rows*rows);
+ for (i=0;i<rows;i++) eigenvalues[i+i*rows]=DoubleComplex(outReal[i],outImag[i]);
+
+
+ free(inCopy);
+ free(outReal);
+ free(outImag);
+ free(pdblWork);
+ free(pdblLeftvectors);
+ free(pdblRightvectors);
+}
+