2019-03-18 12:47:47 -0500 received badge ● Popular Question (source) 2018-08-31 12:45:16 -0500 commented answer Sage could be even more clever - How to force the use of 'sympy' backend for simplifying symbolic integrals? Thanks, that was the workaround I was looking for! 2018-08-16 12:02:38 -0500 commented answer Solved: Why does integrate(psi(y)*f(y),y) return an error but integrate(psi(t,y)*f(t,y),y) works? That's good to know, I'll take it as an exception then -- and nothing better to understand the software then a bug being explained! 2018-08-16 11:56:40 -0500 commented answer Solved: Why does integrate(psi(y)*f(y),y) return an error but integrate(psi(t,y)*f(t,y),y) works? seems to be a whitespace indent Found it! 2018-08-16 11:54:20 -0500 asked a question Sage could be even more clever - How to force the use of 'sympy' backend for simplifying symbolic integrals? Hi there, I have noticed the following problem: sage: f = function('f')(x) sage: var('h') sage: integrate(exp(h)*exp(x)*f(x),x) integrate(e^(h + x)*f(x), x)  The workaround seems to be using the sympy backend for symbolic integration sage: integrate(exp(h)*exp(x)*f(x),x,algorithm='sympy') e^h*integrate(e^x*f(x), x)  which always seems to be a good idea as I learned from @Emmanuel Charpentier over here. Now I would like to force the use of algorith='sympy' for simplifying these integrate(...) expressions globally. Unfortunately, the simplify() command does not allow to set this option. sage: integrate(exp(h)*exp(x)*f(x),x) integrate(e^(h + x)*f(x), x) sage: _.simplify() integrate(e^(h + x)*f(x), x)  TL;DR How can I force sage to pull out these type of exponential constants from the integral with the simplify() command? 2018-08-16 10:50:40 -0500 received badge ● Good Question (source) 2018-08-16 10:37:46 -0500 commented answer Solved: Why does integrate(psi(y)*f(y),y) return an error but integrate(psi(t,y)*f(t,y),y) works? Thank you for the quick answer! I struggled to format my post -- what are the html tags for the nice verbatim code block? 2018-08-16 10:25:01 -0500 commented answer Solved: Why does integrate(psi(y)*f(y),y) return an error but integrate(psi(t,y)*f(t,y),y) works? Thank you very much, that is a very thorough answer! Just started playing around with SAGE, didn't expect the underlying cracks to show up that quickly.... Do you think I should file another ticket or can I somehow 'push' yours? 2018-08-16 10:21:58 -0500 received badge ● Supporter (source) 2018-08-16 10:21:46 -0500 received badge ● Scholar (source) 2018-08-13 12:12:26 -0500 received badge ● Nice Question (source) 2018-08-08 08:33:05 -0500 received badge ● Editor (source) 2018-08-08 07:43:48 -0500 received badge ● Student (source) 2018-08-08 07:23:22 -0500 asked a question Solved: Why does integrate(psi(y)*f(y),y) return an error but integrate(psi(t,y)*f(t,y),y) works? Hi there, I am trying get an symbolic expression for the convolution $$(\psi \star f)(x) := \int\limits_{\mathbb{R}} \psi(x-y) f(y) {d y}$$ of two functions $f, \psi: \mathbb{R} \to \mathbb{R}$ as follows:  var('y') psi = function('psi')(y) f = function('f')(y) integrate(psi(x-y)*f(y),y)  upon which I get the error message RuntimeError: ECL says: Error executing code in Maxima: If I add an extra argument to the two functions and define them as $$f, \psi : \mathbb{R} \times \mathbb{R} \to \mathbb{R}$$ as follows:  var('t') psi = function('psi')(t,y) f = function('f')(t,y) integrate(psi(t,x-y)*f(t,y),y)  there is a surprise, it suddenly works! I get the desired symbolic expression on which I can run diff(..,x) and all the other built-in functions. TL;DR Why does integrate(psi(y)*f(y),y) return an error? Solution Use sympy backend for symbolic integration as in integrate(psi(x-y)*f(y),y, algorithm="sympy")