From 43f7bede8fc85e87870bb705ff6422e5650031a5 Mon Sep 17 00:00:00 2001
From: Francesco Lannutti <nicolati@users.sf.net>
Date: Sat, 14 Mar 2020 23:21:26 +0100
Subject: [PATCH] Added the support for .ic statement in KLU mode

---
 src/maths/KLU/klusmp.c        | 37 +++++++++++++++++++++++++++--------
 src/spicelib/analysis/cktic.c | 21 +++++++++++++++++---
 2 files changed, 47 insertions(+), 11 deletions(-)

diff --git a/src/maths/KLU/klusmp.c b/src/maths/KLU/klusmp.c
index 1725fc8da..a22c4669d 100644
--- a/src/maths/KLU/klusmp.c
+++ b/src/maths/KLU/klusmp.c
@@ -997,15 +997,36 @@ SMPelement *
 SMPfindElt (SMPmatrix *eMatrix, int Row, int Col, int CreateIfMissing)
 {
     MatrixPtr Matrix = eMatrix->SPmatrix ;
-    ElementPtr Element ;
 
-    /* Begin `SMPfindElt'. */
-    assert (IS_SPARSE (Matrix)) ;
-    Row = Matrix->ExtToIntRowMap [Row] ;
-    Col = Matrix->ExtToIntColMap [Col] ;
-    Element = Matrix->FirstInCol [Col] ;
-    Element = spcFindElementInCol (Matrix, &Element, Row, Col, CreateIfMissing) ;
-    return (SMPelement *)Element ;
+    if (eMatrix->CKTkluMODE)
+    {
+        int i ;
+
+        Row = Matrix->ExtToIntRowMap [Row] ;
+        Col = Matrix->ExtToIntColMap [Col] ;
+        for (i = eMatrix->CKTkluAp [Col - 1] ; i < eMatrix->CKTkluAp [Col] ; i++) {
+            if (eMatrix->CKTkluAi [i] == Row - 1) {
+                if (eMatrix->CKTkluMatrixIsComplex == CKTkluMatrixReal) {
+                    return (SMPelement *) &(eMatrix->CKTkluAx [i]) ;
+                } else if (eMatrix->CKTkluMatrixIsComplex == CKTkluMatrixComplex) {
+                    return (SMPelement *) &(eMatrix->CKTkluAx_Complex [2 * i]) ;
+                } else {
+                    return NULL ;
+                }
+            }
+        }
+        return NULL ;
+    } else {
+        ElementPtr Element ;
+
+        /* Begin `SMPfindElt'. */
+        assert (IS_SPARSE (Matrix)) ;
+        Row = Matrix->ExtToIntRowMap [Row] ;
+        Col = Matrix->ExtToIntColMap [Col] ;
+        Element = Matrix->FirstInCol [Col] ;
+        Element = spcFindElementInCol (Matrix, &Element, Row, Col, CreateIfMissing) ;
+        return (SMPelement *)Element ;
+    }
 }
 
 /* XXX The following should probably be implemented in spUtils */
diff --git a/src/spicelib/analysis/cktic.c b/src/spicelib/analysis/cktic.c
index 194b29ade..448a6fcd0 100644
--- a/src/spicelib/analysis/cktic.c
+++ b/src/spicelib/analysis/cktic.c
@@ -25,15 +25,30 @@ CKTic(CKTcircuit *ckt)
 
     for(node = ckt->CKTnodes;node != NULL; node = node->next) {
         if(node->nsGiven) {
-            node->ptr = SMPmakeElt(ckt->CKTmatrix,node->number,node->number);
+            if (ckt->CKTkluMODE) {
+                node->ptr = (double *) SMPfindElt (ckt->CKTmatrix, node->number, node->number, 0) ;
+                if (node->ptr == NULL) {
+                    printf ("Warning: The needed element doesn't exist in the matrix, but KLU mode cannot create a new element. ") ;
+                    printf ("Please specify an existing element for .nodeset\n") ;
+                }
+            } else {
+                node->ptr = SMPmakeElt(ckt->CKTmatrix,node->number,node->number);
+            }
             if(node->ptr == NULL) return(E_NOMEM);
             ckt->CKThadNodeset = 1;
             ckt->CKTrhsOld[node->number] = ckt->CKTrhs[node->number] = node->nodeset;
         }
         if(node->icGiven) {
             if(! ( node->ptr)) {
-                node->ptr = SMPmakeElt(ckt->CKTmatrix,node->number,
-                        node->number);
+                if (ckt->CKTkluMODE) {
+                    node->ptr = (double *) SMPfindElt (ckt->CKTmatrix, node->number, node->number, 0) ;
+                    if (node->ptr == NULL) {
+                        printf ("Warning: The needed element doesn't exist in the matrix, but KLU mode cannot create a new element. ") ;
+                        printf ("Please specify an existing element for .ic\n") ;
+                    }
+                } else {
+                    node->ptr = SMPmakeElt(ckt->CKTmatrix,node->number, node->number);
+                }
                 if(node->ptr == NULL) return(E_NOMEM);
             }
             ckt->CKTrhsOld[node->number] = ckt->CKTrhs[node->number] = node->ic;