[SciPy-user] accuracy of stats.gamma.pdf

Nicolas CHOPIN nicolas.chopin@bristol.ac...
Thu Jan 29 07:40:19 CST 2009


Pauli Virtanen <pav <at> iki.fi> writes:

> 
> Thu, 29 Jan 2009 12:52:37 +0000, Pauli Virtanen wrote:
> [clip]
> > It appears that scipy.stats.gamma doesn't have a scale parameter.
> 
> Oops, obviously it has a scale parameter:
> 
> In Scipy:
> >>> scipy.stats.gamma.pdf(5, 2, 0, 1.0/5)
> 1.7359929831205026e-09
> 
> In R:
> > dgamma(5,2,5)
> [1] 1.735993e-09
> 
> So, no bugs present, just different order of arguments.
> 


oops, many thanks, I managed to misunderstand both R and scipy.stats syntaxes,
sorry...
A poor excuse is that in my field Gamma(a,b) distributions refers to Gamma with
shape a, and scale=1/b, and nobody uses a location parameter.
Thanks again



More information about the SciPy-user mailing list