sys3x3_with_tol

Mesh/2D_Mesh.cpp

-/* $Id: 2D_Mesh.cpp,v 1.12 2000-12-13 20:21:48 geuzaine Exp $ */
+/* $Id: 2D_Mesh.cpp,v 1.13 2000-12-18 08:31:58 geuzaine Exp $ */
 /*
    Maillage Delaunay d'une surface (Point insertion Technique)
 
@@ -168,7 +168,7 @@ void Plan_Moyen (void *data, void *dum){
 
   /* by + cz = -x */
 
-  else if (!sys3x3 (sys, b, res, &det)){
+  else if (!sys3x3_with_tol (sys, b, res, &det)){
     s->d = 0.0;
     s2s[0][0] = sys[1][1];
     s2s[0][1] = sys[1][2];

Mesh/Numeric.cpp

-/* $Id: Numeric.cpp,v 1.9 2000-12-13 20:27:12 geuzaine Exp $ */
+/* $Id: Numeric.cpp,v 1.10 2000-12-18 08:31:58 geuzaine Exp $ */
 
 #include "Gmsh.h"
 #include "Const.h"
@@ -121,6 +121,20 @@ int sys3x3 (double mat[3][3], double b[3], double res[3], double *det){
 
 }
 
+int sys3x3_with_tol (double mat[3][3], double b[3], double res[3], double *det){
+  int out;
+
+  out = sys3x3(mat,b,res,det);
+
+  if (fabs(*det) < 1.e-12){
+    Msg(INFOS, "Assuming 3x3 Matrix is Singular (Is this OK?)");
+    res[0] = res[1] = res[2] = 0.0 ;
+    return (0);
+  }
+
+  return out ;
+}
+
 int det3x3 (double mat[3][3], double *det){
   *det = mat[0][0] * (mat[1][1] * mat[2][2] - mat[1][2] * mat[2][1]) -
     mat[0][1] * (mat[1][0] * mat[2][2] - mat[1][2] * mat[2][0]) +

Mesh/Numeric.h

-/* $Id: Numeric.h,v 1.3 2000-11-26 15:43:47 geuzaine Exp $ */
+/* $Id: Numeric.h,v 1.4 2000-12-18 08:31:58 geuzaine Exp $ */
 #ifndef _NUMERIC_H_
 #define _NUMERIC_H_
 
@@ -11,6 +11,7 @@ void direction (Vertex * v1, Vertex * v2, double d[3]);
 void Projette (Vertex * v, double mat[3][3]);
 int sys2x2 (double mat[2][2], double b[2], double res[2]);
 int sys3x3 (double mat[3][3], double b[3], double res[3], double *det);
+int sys3x3_with_tol (double mat[3][3], double b[3], double res[3], double *det);
 int det3x3 (double mat[3][3], double *det);
 int inv3x3 (double mat[3][3], double inv[3][3], double *det);
 void find_bestuv (Surface * s, double X, double Y,