Merge pull request #607 from mtmiller/heaviside-test-typo

Fix typo in heaviside test printing an empty plot

Author: cbm755

inst/@sym/heaviside.m

@@ -90,7 +90,7 @@
 
 %!test
 %! if (python_cmd ('return Version(spver) <= Version("1.0")'))
-%! print ('skipping test, sympy too old')
+%! disp ('skipping test, sympy too old')
 %! else
 %! H0 = sym([1 -2 0; 3 0 pi]);
 %! A = heaviside (sym(0), H0);