Thanks for the tip. I've tried .is_Real (capital one), because as IDE says
it's basic method, while .is_real related to Interval. That's why I didnt
even try it
In my opinion, x = Symbol('x', real=True) makes it way better to control
and read, so I'll stick to it.
суббота, 2 ноября 2013 г., 20:31:39 UTC+4 пользователь Aaron Meurer написал:
>
> The issue is that the second and third solution give None, which means
> it doesn't know (there's really no good reason for this, but you
> generally have to look out for that). Really, those solutions should
> be complex.
>
> The attribute you want is is_real.
>
> Another thing you can do is to set x to be real. If you do that, solve
> will filter out the solutions automatically
>
> In [52]: x = Symbol('x', real=True)
>
> In [53]: print(solve(x**3 - 4, x))
> [2**(2/3)]
>
> Aaron Meurer
>
> On Sat, Nov 2, 2013 at 10:17 AM, Alexander Birukov
> <sany...@gmail.com<javascript:>>
> wrote:
> > Hello everyone. I have another question, and as topic name says: how can
> I
> > sort return of solve, so complex numbers wont be in anymore?
> >
> > I've seached in flags for it, but no luck, and then I've played with
> .is_*
> > attributes and got something wierd(?):
> >
> > sols = solve(x**3 - 4)
> > sols = [sol for sol in sols if sol.is_complex]
> >
> > sols before filtering:
> > [2**(2/3), -2**(2/3)/2 - 2**(2/3)*sqrt(3)*I/2, -2**(2/3)/2 +
> > 2**(2/3)*sqrt(3)*I/2]
> >
> > after:
> > 2**(2/3)
> >
> > Question is why and does that code always gives me what I want? (Just
> > confused about why is_complex returns True for real, and False for
> exactly
> > complex number).
> >
> > --
> > You received this message because you are subscribed to the Google
> Groups
> > "sympy" group.
> > To unsubscribe from this group and stop receiving emails from it, send
> an
> > email to sympy+un...@googlegroups.com <javascript:>.
> > To post to this group, send email to sy...@googlegroups.com<javascript:>.
>
> > Visit this group at http://groups.google.com/group/sympy.
> > For more options, visit https://groups.google.com/groups/opt_out.
>
--
You received this message because you are subscribed to the Google Groups
"sympy" group.
To unsubscribe from this group and stop receiving emails from it, send an email
to sympy+unsubscr...@googlegroups.com.
To post to this group, send email to sympy@googlegroups.com.
Visit this group at http://groups.google.com/group/sympy.
For more options, visit https://groups.google.com/groups/opt_out.
