[SciPy-User] from 50% probablity value to standard deviation

[Johannes Radinger]

Hello SciPy-People,

I have got a normal distribution with μ=0 and I know that 50% of all
observations
are within a certain range (50% probability are between -x and +x).
How can I get the standard deviation of that normal distribution?
Usually 68,3 % are within one SD. How is it possible to calculate the
SD from my 50% value? Is there any conversion factor I can use? Can
that be simply and exactly calculated with Scipy?

Thank you

/Johannes