MaplePrimes - answers and comments on Question, Why isn't maple integrating this?

assume

Preben Alsholm — Sat, 26 Jan 2013 22:08:30 Z

Remove the second assume command. New assumptions cancel previous ones.

I find it more convenient not to use assume at all. I use assuming instead:

restart;
f_exp:=exp(-alph*r^2);
ff_deriv:=r^2*f_exp^2;
ff:=int(ff_deriv,r=0..infinity) assuming alph>0;
#assuming makes assumptions during that last computation only.

Assumptions are not cumulative

Carl Love — Sat, 26 Jan 2013 22:12:45 Z

Assumptions via assume on one variable are not cumulative. Your second assume command erases the effect of the first. The second one is unnecessary anyway: It is implied by the first. If you actually want to make multiple assumptions on a single variable, put them together in one assume command or use the additionally command. See the examples at ?assume for details. If you remove the second assume, you will get your expected result.

By the way, you misspelled alpha as alph, but that doesn't change the result.

I agree with Preben about assuming. I think that it makes for cleaner, easier-to-read, less-error-prone, and more-flexible worksheets. Although there is still a place for assume if you're trying to get Maple to do a symbolic proof.

Thank you! Makes sense :)

starryskiesx — Sat, 26 Jan 2013 23:13:00 Z

Thank you! Makes sense :)

another place

Alejandro Jakubi — Sun, 27 Jan 2013 05:41:28 Z

Another place is stated at the end of ?assuming,details > Description:

The assuming command does not scan Maple programs regarding the potential presence of assumed variables. To compute taking into account assumptions on variables found in the bodies of programs, use assume.