substitute values in Maple?

[Luna Moon]

Hi all,

I set alpha = 2 in Maple.

And I thought all the following expressions involving alpha should be
automatically changed to 2. But it didn't happen. All expressions
still show alpha instead of 2.

What shall I do?

Thanks a lot!

[Axel Vogt]

alpha := 2;
------^----

[Luna Moon]

That worked. Thanks a lot!

[Ray Vickson]

Another way is to use the command 'subs(alpha=2,expr)' to make alpha =
2 in your expression 'expr'. Sometimes this is better than using the
method 'alpha:=2', because this last method changes alpha to 2
*everywhere* in your worksheet, and sometimes that is not what you
want. By using the 'subs' method instead, alpha will still be symbolic
as soon as the substitution/evaluation has been made.

R.G. Vickson

[Axel Vogt]

Yes. Or 'eval(expr, alpha=2)'.