Index: trunk/psLib/src/imageops/psImageMapFit.c
===================================================================
--- trunk/psLib/src/imageops/psImageMapFit.c	(revision 37806)
+++ trunk/psLib/src/imageops/psImageMapFit.c	(revision 37811)
@@ -286,9 +286,16 @@
     // fprintf (stderr, "Total: %f\n", Total);
 
+    double MaxPivot = 0.0;
+    for (int i = 0; i < Nx*Ny; i++) {
+      MaxPivot = PS_MAX(MaxPivot, fabs(A->data.F32[i][i]));
+      // fprintf (stderr, "piv, max: %f : %f\n", A->data.F32[i][i], MaxPivot);
+    }
+
     // test for empty diagonal elements (unconstained cells), mark, and set pivots to 1.0
     psVector *Empty = psVectorAlloc (Nx*Ny, PS_TYPE_S8);
     psVectorInit (Empty, 0);
+    double MinPivot = 0.025*MaxPivot;
     for (int i = 0; i < Nx*Ny; i++) {
-        if (A->data.F32[i][i] == 0.0) {
+      if (fabs(A->data.F32[i][i]) < MinPivot) {
             Empty->data.S8[i] = 1;
             for (int j = 0; j < Nx*Ny; j++) {