From 64b43b0c68d04f4104fa669f6398caab24002dcd Mon Sep 17 00:00:00 2001
From: rlar <rlar>
Date: Sat, 26 Dec 2015 19:44:41 +0100
Subject: [PATCH] plotting/plotit.c, xtend(), #4/7 support vector of zero
 length

---
 src/frontend/plotting/plotit.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/src/frontend/plotting/plotit.c b/src/frontend/plotting/plotit.c
index 06e588a1d..7b6547b08 100644
--- a/src/frontend/plotting/plotit.c
+++ b/src/frontend/plotting/plotit.c
@@ -97,21 +97,25 @@ xtend(struct dvec *v, int length)
     }
 
     if (isreal(v)) {
+        double d = NAN;
         od = v->v_realdata;
         v->v_realdata = TMALLOC(double, length);
         for (i = 0; i < v->v_length; i++)
             v->v_realdata[i] = od[i];
-        d = od[i - 1];
+        if (i > 0)
+            d = od[i - 1];
         tfree(od);
         while (i < length)
             v->v_realdata[i++] = d;
     } else {
+        ngcomplex_t c = {NAN, NAN};
         oc = v->v_compdata;
         v->v_compdata = TMALLOC(ngcomplex_t, length);
         for (i = 0; i < v->v_length; i++) {
             v->v_compdata[i] = oc[i];
         }
-        c = oc[i - 1];
+        if (i > 0)
+            c = oc[i - 1];
         tfree(oc);
         while (i < length)
             v->v_compdata[i++] = c;