python - What are the loc and scale parameters in scipy.stats.maxwell? -

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the maxwell-boltzmann distribution given maxwell-boltzmann http://mathworld.wolfram.com/images/equations/maxwelldistribution/inline9.gif. scipy.stats.maxwell distribution uses loc , scale parameters define distribution. how parameters in 2 definitions connected? appreciate if tell in general how determine relation between parameters in scipy.stats , usual definition.

the loc parameter always shifts x variable. in other words, generalizes distribution allow shifting x=0 x=loc. when loc nonzero,

maxwell.pdf(x) = sqrt(2/pi)x**2 * exp(-x**2/2), x > 0

becomes

maxwell.pdf(x, loc) = sqrt(2/pi)(x-loc)**2 * exp(-(x-loc)**2/2), x > loc.

the doc string scipy.stats.maxwell states:

a special case of chi distribution, df = 3, loc = 0.0, , given scale = a, a parameter used in mathworld description.

so scale corresponds parameter a in equation

http://mathworld.wolfram.com/images/equations/maxwelldistribution/inline9.gif

in general need read distribution's doc string know parameters distribution has. the beta distribution, example, has a , b shape parameters in addition loc , scale.

however, believe continuous distributions, distribution.pdf(x, loc, scale) identically equivalent distribution.pdf(y) / scale y = (x - loc) / scale.


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