On Tue, Dec 2, 2008 at 1:07 PM, Neal Becker <[EMAIL PROTECTED]> wrote:
>
> I tried some simple algebra, but I'm not getting the result I expected (or
> given by macsyma).
>
> The problem is to invert the Normal distribution:
>
> In [11]: solve (Eq (1/(sqrt(2*pi)*s) * exp (-(x**2)/(2*(s**2))),y), x)
> Out[11]: [I*2**(1/2)*(s**2)**(1/2)*log(s*y*2**(1/2)*pi**(1/2))**(1/2)]
>
> The expected answer is sqrt(-2 s**2 log(sqrt(2 pi) s y)

Well, it's the same thing, only sqrt(-2) is rewritten as I*sqrt(2) and
also instead of things like sqrt(a*b*c) you got
sqrt(a)*sqrt(b)*sqrt(c).

So what you want is some way to convert between sqrt(-2) and
I*sqrt(2), e.g. in general between sqrt(a*b*c) and
sqrt(a)*sqrt(b)*sqrt(c)?
Yes, I think it's worthy. Could you please create an issue for that?

Thanks,
Ondrej

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