Revision history [back]
 | 1 | initial version |
Symbolic expressions is a big bundle of stuff. For example, you can notice that pi is also symbolic expression:
sage: type(pi)
<type 'sage.symbolic.expression.Expression'>
Some equations are also symbolic expressions:
sage: type(x^2 + 1 == x)
<type 'sage.symbolic.expression.Expression'>
You can notice, that g and h have the same type, but not the same parent:
sage: g.parent()
Callable function ring with arguments (x, y)
sage: h.parent()
Symbolic Ring
Since g is callable, the way to evaluate it is supposed to be:
sage: g(0,1)
1
If you want do deal uniformly with g and h, you can use the .subs() method:
sage: h.subs({x:0,y:1})
1
sage: g.subs({x:0,y:1})
(x, y) |--> 1
