From 8b80a4454a34c689c423d43f654d2b1a9b2e5a6b Mon Sep 17 00:00:00 2001
From: Holger Vogt <holger.vogt@uni-due.de>
Date: Wed, 10 Dec 2025 22:00:36 +0100
Subject: [PATCH] Add and fill hbnumfreqs[10] as integer array for up to 10
 numbers of frequencies for HB

---
 src/frontend/options.c          | 32 +++++++++++++++++++++++++++++++-
 src/frontend/spiceif.c          |  2 ++
 src/include/ngspice/optdefs.h   |  4 ++++
 src/spicelib/analysis/cktsopt.c | 25 +++++++++++++++++++++++++
 4 files changed, 62 insertions(+), 1 deletion(-)

diff --git a/src/frontend/options.c b/src/frontend/options.c
index 7dfe6f97a..093f62b84 100644
--- a/src/frontend/options.c
+++ b/src/frontend/options.c
@@ -26,6 +26,8 @@ bool ft_nodesprint = FALSE, ft_optsprint = FALSE, ft_noinitprint = FALSE;
 bool ft_norefprint = FALSE, ft_skywaterpdk = FALSE;
 bool ft_ngdebug = FALSE, ft_nginfo = FALSE, ft_stricterror = FALSE, ft_spiniterror = FALSE;
 
+int hbnumfreqs[10];
+
 static void setdb(char *str);
 static struct variable *cp_enqvec_as_var(const char *vec_name,
         int *p_f_found);
@@ -397,8 +399,36 @@ cp_usrset(struct variable *var, bool isset)
         return (US_DONTRECORD);
     } else if (eq(var->va_name, "plots")) {
         return (US_READONLY);
-    }
+    /* Fill in hbnumfreqs[10] by reading from
+    'set hbnumfreq = 7' or 'set hbnumfreq = ( 7, 9 ) 
+     */
+#ifdef WITH_HB
+    } else if (eq(var->va_name, "hbnumfreq")) {
+        if (var->va_type == CP_NUM) {
+            hbnumfreqs[0] = var->va_num;
+            for (int ii = 1; ii < 10; ii++)
+                hbnumfreqs[ii] = 0;
+        }
+        else if (var->va_type == CP_LIST) {
+            int ii = 0;
+            for (tv = var->va_vlist; tv; tv = tv->va_next)
+                if (tv->va_type == CP_NUM) {
+                    if (ii > 9) {
+                        fprintf(stderr, "Warning: too many frequencies (> 10), ignored\n");
+                        break;
+                    }
+                    hbnumfreqs[ii] = tv->va_num;
+                    ii++;
+                }
+                else
+                    fprintf(cp_err, "Error: bad syntax for hbnumfreq\n");
+            for (int jj = ii; jj < 10; jj++)
+                hbnumfreqs[jj] = 0;
+        }
 
+        return (US_OK);
+    }
+#endif
     if (plot_cur)
         for (tv = plot_cur->pl_env; tv; tv = tv->va_next)
             if (eq(tv->va_name, var->va_name))
diff --git a/src/frontend/spiceif.c b/src/frontend/spiceif.c
index 9697d7298..5b9689344 100644
--- a/src/frontend/spiceif.c
+++ b/src/frontend/spiceif.c
@@ -467,6 +467,8 @@ if_option(CKTcircuit *ckt, char *name, enum cp_types type, void *value)
     } else if (eq(name, "nomod")) {
         ft_nomod = TRUE;
         return 0;
+    } else if (eq(name, "hbnumfreq")) {
+        return 0;
     }
 
     which = ft_find_analysis("options");
diff --git a/src/include/ngspice/optdefs.h b/src/include/ngspice/optdefs.h
index 3455a2454..14d60ed4f 100644
--- a/src/include/ngspice/optdefs.h
+++ b/src/include/ngspice/optdefs.h
@@ -126,6 +126,10 @@ enum {
     OPT_EPSMIN,
     OPT_CSHUNT,
 
+#ifdef WITH_HB
+    OPT_HBNF,
+#endif
+
 #ifdef KLU
     OPT_SPARSE,
     OPT_KLU,
diff --git a/src/spicelib/analysis/cktsopt.c b/src/spicelib/analysis/cktsopt.c
index 0c1f723e1..9da0a6835 100644
--- a/src/spicelib/analysis/cktsopt.c
+++ b/src/spicelib/analysis/cktsopt.c
@@ -28,6 +28,10 @@ Modified: 2000 AlansFixes
 /* gtri - end - wbk - add includes */
 #endif
 
+#ifdef WITH_HB
+extern int hbnumfreqs[10];
+#endif
+
 /* ARGSUSED */
 int
 CKTsetOpt(CKTcircuit *ckt, JOB *anal, int opt, IFvalue *val)
@@ -188,6 +192,22 @@ CKTsetOpt(CKTcircuit *ckt, JOB *anal, int opt, IFvalue *val)
         break;
 #endif
 
+#ifdef WITH_HB
+        /* called here from .options with parameters only */
+    case OPT_HBNF:
+    {
+        int* inf = val->v.vec.iVec;
+        if (hbnumfreqs[0] == 0) {
+            /* not yet set, cannot overwrite */
+            for (int ii = 0; ii < val->v.numValue && ii < 10; ii++) {
+                hbnumfreqs[ii] = inf[ii];
+            }
+        }
+
+        break;
+    }
+#endif
+
 /* gtri - begin - wbk - add new options */
 #ifdef XSPICE
     case OPT_EVT_MAX_OP_ALTER:
@@ -347,6 +367,11 @@ static IFparm OPTtbl[] = {
  { "epsmin", OPT_EPSMIN, IF_SET|IF_REAL,
         "Minimum value for log" },
 
+#ifdef WITH_HB
+ { "hbnumfreq", OPT_HBNF, IF_SET|IF_INTVEC,
+        "Number of harmonics for HB" },
+#endif
+
 #ifdef KLU
  { "sparse", OPT_SPARSE, IF_SET|IF_FLAG,
         "Set SPARSE 1.3 as Direct Linear Solver" },