why this integral fail using "fricas" algorithm?
Using sagemath 8.9 on Linux, with Fricas 1.5 installed
>sage
┌────────────────────────────────────────────────────────────────────┐
│ SageMath version 8.9, Release Date: 2019-09-29 │
│ Using Python 2.7.16. Type "help()" for help. │
└────────────────────────────────────────────────────────────────────┘
sage: var('x')
x
sage: integrate(sqrt(2)*x^2 + 2*x,x, algorithm="fricas")
File "<string>", line unknown
SyntaxError: Malformed expression
sage: integrate(sqrt(2)*x^2 + 2*x,x, algorithm="maxima")
1/3*sqrt(2)*x^3 + x^2But it works when using Fricas 1.5 directly
2) -> ii:=integrate(sqrt(2)*x^2 + 2*x,x);
Type: Polynomial(AlgebraicNumber)
(3) -> unparse(ii::InputForm)
(3) "((2^(1/2))/3)::AlgebraicNumber()*x^3+1::AlgebraicNumber()*x^2"
Type: StringIs this a bug in the sagemath <---> Fricas interface?
Thanks --Nasser
There is a problem in the conversion back to sage
This can be traced to the following bug
It's worse than that (on Python3-based Sage 9.0.beta1):
This lets think that Sage has stored the "character representation" of t as its value, rather than a FriCAS expression.
It seems distinct from Trac28630. It might be related to Trac#27268.
Inn any case, the Sage<-->Fricas interface seems to need revision.