X-Git-Url: https://www.ginac.de/ginac.git//ginac.git?p=ginac.git;a=blobdiff_plain;f=doc%2Ftutorial%2Fginac.texi;h=81bfb7f7b4725b573b2fcf39f87026a5fd72d75b;hp=4794837657af188b83c7b9ce68097b2ee01bcb8d;hb=307c6f9e8ad1d0545ffc17f6bec024a4c10b98c0;hpb=36c5241d290222f71d501b253e3bbe3097221645

diff --git a/doc/tutorial/ginac.texi b/doc/tutorial/ginac.texi
index 47948376..81bfb7f7 100644
--- a/doc/tutorial/ginac.texi
+++ b/doc/tutorial/ginac.texi
@@ -4437,7 +4437,10 @@ function that does so, in this case the one in class @code{numeric}:
 @example
 static ex cos_evalf(const ex & x)
 @{
-    return cos(ex_to<numeric>(x));
+    if (is_a<numeric>(x))
+        return cos(ex_to<numeric>(x));
+    else
+        return cos(x).hold();
 @}
 @end example