Hi ab0c1d0ef,

On Fri, Jul 11, 2014 at 11:02 AM,  <[email protected]> wrote:
> Dear user and developers,
>
> I'm new to sympy and tried a few things out, of course I stumbled across
> smth I coudln't understand.
> So here is my question:
>
> If I define an expression like
> g=sqrt(a/pi)*exp(-a*x**2)
> and integrate it like
> integrate(g,(x,-oo,oo))
> I get the expected result (1).
>
> But if I integrate an expression like
> g=sqrt(1/a/pi)*exp(-x**2/a)
> and integrate it the same way I get
> ( a * sqrt(1/a) ) / sqrt(polar_lift(a))
>
> I must admit I'm a little bit frightened by the polar_lift function because
> I've never heard of it, but it seems to give the argument of a complex
> number. Is this correct?
> But then I don't understand why for
> a=Symbol('a',real=True)
> g=sqrt(1/a/pi)*exp(-x**2/a)
> simplify(integrate(g,(x,-oo,oo)))
> I still don't get 1 as a result.

Thanks for reporting this, I think you might have discovered a bug.
Btw, this is what I get with the latest master:

https://gist.github.com/certik/cd8cd4c0a7f0ba04c719

But it still shows the behavior you described.

Ondrej

>
> Would be nice to know.
> Thanks in advance.
>
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