# scipy.special.pdtri¶

scipy.special.pdtri(k, y) = <ufunc 'pdtri'>

Inverse to pdtr vs m

Returns the Poisson variable m such that the sum from 0 to k of the Poisson density is equal to the given probability y: calculated by gammaincinv(k+1, y). k must be a nonnegative integer and y between 0 and 1.

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