From e6ba6e9161124c6ae041b26d369c961a97cf080a Mon Sep 17 00:00:00 2001
From: torset
Date: Thu, 11 Dec 2008 15:12:01 +0000
Subject: Add determ

---
 src/matrixOperations/determ/ddeterma.c | 93 ++++++++++++++++++++++++++++++++++
 1 file changed, 93 insertions(+)
 create mode 100644 src/matrixOperations/determ/ddeterma.c

(limited to 'src/matrixOperations/determ/ddeterma.c')

diff --git a/src/matrixOperations/determ/ddeterma.c b/src/matrixOperations/determ/ddeterma.c
new file mode 100644
index 00000000..75ee6ed9
--- /dev/null
+++ b/src/matrixOperations/determ/ddeterma.c
@@ -0,0 +1,93 @@
+/*
+ *  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
+ *
+ */
+
+
+#ifndef WITHOUT_LAPACK
+#include "lapack.h"
+#endif
+#include "determ.h"
+#include <malloc.h>
+#include "lapack.h"
+#include <stdio.h>
+
+
+double ddeterma(double * in, int size){
+#ifndef WITHOUT_LAPACK
+	int i=0, info=0;
+	double out=0;
+	double *inCopy=NULL;
+	int* tmp=NULL;
+	
+	/*Calculation of the determinant*/
+	switch (size){
+		case 2 : out = in[0]*in[3]-in[1]*in[2];
+			 break;
+		case 3 : /*regle de Sarrus*/
+			 out = in[0]*in[4]*in[8]+in[1]*in[5]*in[6]+in[2]*in[3]*in[7]
+			      -in[0]*in[5]*in[7]-in[1]*in[3]*in[8]-in[2]*in[4]*in[6];
+			 break;
+		default : 
+		
+			  /*Copy the input matrix*/
+			  inCopy=malloc((uint)(size*size)*sizeof(double));
+			  for (i=0;i<size*size;i++) inCopy[i]=in[i];
+
+			  tmp=malloc((uint)size*sizeof(int));			  
+			  dgetrf_(&size, &size, inCopy, &size, tmp, &info);
+			  out=1;
+			  for (i=0;i<size;i++){
+			  	if (tmp[i]!=i+1) out=-out;
+			  	out=inCopy[i*(size+1)]*out;
+			  }
+			  free(tmp);
+			  free(inCopy);
+			  break;
+	}
+	
+#else
+	int i=0, j=0, k=0;
+	double out=0, pivot=0;
+	double *inCopy=NULL;
+	
+	/*Calculation of the determinant*/
+	switch (size){
+		case 2 : out = in[0]*in[3]-in[1]*in[2];
+			 break;
+		case 3 : /*regle de Sarrus*/
+			 out = in[0]*in[4]*in[8]+in[1]*in[5]*in[6]+in[2]*in[3]*in[7]
+			      -in[0]*in[5]*in[7]-in[1]*in[3]*in[8]-in[2]*in[4]*in[6];
+			 break;
+		default : 
+				
+				  /*Copy the input matrix*/
+			  inCopy=malloc((uint)(size*size)*sizeof(double));
+			  for (i=0;i<size*size;i++) inCopy[i]=in[i];
+			  
+    			  for (i=0;i<size;i++){
+				for (j=i+1;j<size;j++){
+					pivot = inCopy[i*size+j]/inCopy[i*size+i];
+					for (k=0;k<size-i;k++){
+						inCopy[i*size+j+k*size]-=pivot*inCopy[i*size+i+k*size];
+					}
+				}
+			  }
+			  out=1;
+			  for (i=0;i<size;i++){
+			  	out *= inCopy[i*size+i];
+			  }
+		
+	}
+#endif
+
+
+	return out;	
+}
-- 
cgit