bugfix, fix sensitvity calculation (for the dc-2+.cir testcase)

ChangeLog

@@ -1,3 +1,7 @@
+2011-04-09  Robert Larice
+ * src/spicelib/analysis/cktsens.c :
+    bugfix, fix sensitvity calculation (for the dc-2+.cir testcase)
+
 2011-04-02  Robert Larice
  * src/frontend/plotting/x11.c :
    extend the fix from 2011-02-11
@@ -12,11 +16,11 @@
  * frontend/typedefs.c, outitf.c: bug no. 3214252 fixed
 
 2011-03-16 Dietmar Warning
- * plotit.c: fix the wrong x-axis label for temp-sweep and res-sweep by 
+ * plotit.c: fix the wrong x-axis label for temp-sweep and res-sweep by
    using macros SV_XXX for vector types
 
 2011-03-13 Dietmar Warning
- * analysis.h, typedefs.h, misc. bXtemp.c: skip printout in bsimtemp for 
+ * analysis.h, typedefs.h, misc. bXtemp.c: skip printout in bsimtemp for
    sens analysis
  * bsim2/bsim2def.h: int for XPARTS flag in ancient debug usage
 

src/spicelib/analysis/cktsens.c

@@ -496,6 +496,14 @@ int sens_sens(CKTcircuit *ckt, int restart)
 			/* Solve; Y already factored */
 			spSolve(Y, delta_I, delta_I, delta_iI, delta_iI);
 
+                        /* the special `0' node
+                        *    the matrix indizes are [1..n]
+                        *    yet the vector indizes are [0..n]
+                        *    with [0] being implicit === 0
+                        */
+                        delta_I[0]  = 0.0;
+                        delta_iI[0] = 0.0;
+
 #ifdef ASDEBUG
 			DEBUG(2) {
 				for (j = 1; j < size; j++) {