Fixed KLU returns values so that NIiter can Factor again, if the matrix is numerically singular from the refactorization

Fixed the NIiter code to perform a factorization without reloading the matrix

src/maths/KLU/klusmp.c

@@ -568,6 +568,7 @@ SMPcReorder (SMPmatrix *Matrix, double PivTol, double PivRel, int *NumSwaps)
         } else {
             if (Matrix->CKTkluCommon->status == KLU_SINGULAR) {
                 fprintf (stderr, "Warning: KLU Matrix is SINGULAR\n") ;
+                return E_SINGULAR ;
             }
             return 0 ;
         }
@@ -614,6 +615,7 @@ SMPreorder (SMPmatrix *Matrix, double PivTol, double PivRel, double Gmin)
         } else {
             if (Matrix->CKTkluCommon->status == KLU_SINGULAR) {
                 fprintf (stderr, "Warning: KLU Matrix is SINGULAR\n") ;
+                return E_SINGULAR ;
             }
             return 0 ;
         }
@@ -673,6 +675,7 @@ SMPreorderKLUforCIDER (SMPmatrix *Matrix)
         } else {
             if (Matrix->CKTkluCommon->status == KLU_SINGULAR) {
                 fprintf (stderr, "Warning (CIDER): KLU Matrix is SINGULAR\n") ;
+                return E_SINGULAR ;
             }
             return 0 ;
         }

src/maths/ni/niiter.c

@@ -145,9 +145,20 @@ NIiter(CKTcircuit *ckt, int maxIter)
                     SPfrontEnd->IFseconds() - startTime;
                 if (error) {
                     if (error == E_SINGULAR) {
+
+#ifdef KLU
+                        error = SMPreorder(ckt->CKTmatrix, ckt->CKTpivotAbsTol, ckt->CKTpivotRelTol, ckt->CKTdiagGmin);
+                        ckt->CKTstat->STATreorderTime += SPfrontEnd->IFseconds() - startTime;
+                        if (error) {
+                            SMPgetError(ckt->CKTmatrix, &i, &j);
+                            SPfrontEnd->IFerrorf (ERR_WARNING, "singular matrix:  check nodes %s and %s\n", NODENAME(ckt, i), NODENAME(ckt, j));
+                        }
+#else
                         ckt->CKTniState |= NISHOULDREORDER;
                         DEBUGMSG(" forced reordering....\n");
                         continue;
+#endif
+
                     }
                     /* CKTload(ckt); */
                     /* SMPprint(ckt->CKTmatrix, stdout); */