Thanks for your welcome. :) Again, I agree with Vinzent.
Sometimes, it's ok to work in, say, C, and then, finally, select only real solutions. It's typically the case when you search for roots of polynomials. But there're other times you simply can't do that. For example, solving inequalities in C, like 2x+7<3x+5, and then restricting to R has no meaning at all. In any case, I find also more intuitive to start with assumptions, before solving (probably because I always teach to my pupils to use quantifiers to indicate where you work, before starting to calculate...). On 27 jan, 20:24, Ondrej Certik <ond...@certik.cz> wrote: > >> If, on the other hand, we don't have global assumptions, I don't think > >> you need to use 'assume(x in R)' at every step. All you have to do is > >> to refine the final answer, e.g. one command. > > > Mathematically the first step is to define the symbols (n in N etc.). > > Moving this to the last step seems counter-intuitive to me. > > That's interesting, because at least for me it is actually very > intuitive to just write the equation and only then worry about > domains/assumptions, if that is needed. > > Anyway, I think we can have both ways. > > Ondrej --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "sympy" group. To post to this group, send email to sympy@googlegroups.com To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sympy?hl=en -~----------~----~----~----~------~----~------~--~---