ASKSAGE: Sage Q&A Forum - RSS feedhttps://ask.sagemath.org/questions/Q&A Forum for SageenCopyright Sage, 2010. Some rights reserved under creative commons license.Thu, 20 Sep 2012 14:05:44 +0200Turn off convergence checking - "formal" integrationhttps://ask.sagemath.org/question/9332/turn-off-convergence-checking-formal-integration/Apologies if something like this has been posted already - I have not found it.
I would like to be able to compute "formal integrals" of functions f(t,x) with respect to x, without having to use assume() to put restrictions on x. In particular, I want to compute `integral(e^(-t)*f,t,0,infinity)`. For example, right now if I try
`integrate(e^(-t)*e^(x*t),t,0,infinity)`
I need to `assume(x < 1)` for it to work. This is fine for simple integrals, but if the function f is more complicated, using `assume()` becomes annoying. I'd like to be able to use a formal integral so that `integrate(e^(-t)*e^(t*f),t,0,infinity)` returns `1/(1 - f)` whenever `f` is a function only of x, without needing to use `assume()` - or an equivalent function.
Thanks!
Edit: It occurred to me that just using integrate(f,t).subs(t=0) seems to work some of the time. I'd still like a better way, though
Thu, 20 Sep 2012 14:05:44 +0200https://ask.sagemath.org/question/9332/turn-off-convergence-checking-formal-integration/