From 431af3246659f993d080c741064b1c1782784925 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Davide=20Sandon=C3=A0?= <sandona.davide@gmail.com>
Date: Sat, 13 Apr 2024 19:00:40 +0200
Subject: [PATCH] added missing variable to example

---
 spb/graphics/functions_3d.py | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/spb/graphics/functions_3d.py b/spb/graphics/functions_3d.py
index b65309e..67f97e5 100644
--- a/spb/graphics/functions_3d.py
+++ b/spb/graphics/functions_3d.py
@@ -504,9 +504,10 @@ def surface(
        from sympy import *
        from spb import *
        import panel as pn
-       x, y, a, b, d, e = symbols("x y a b d e")
+       x, y, a, b, c, d, e = symbols("x y a b c d e")
        graphics(
-           surface(cos(x**2 + y**2) * exp(-(x**2 + y**2) * d),
+           surface(
+               cos(x**2 + y**2) * exp(-(x**2 + y**2) * a),
                prange(x, b, c), prange(y, d, e),
                params={
                    a: (0.25, 0, 1),