scipy.special.pdtri

scipy.special.pdtri(k, y, out=None) = <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.

Parameters

karray_like

Number of occurrences (nonnegative, real)

yarray_like

Probability

outndarray, optional

Optional output array for the function results

Returns

scalar or ndarray

Values of the shape paramter m such that pdtr(k, m) = p

See also

pdtr

Poisson cumulative distribution function

pdtrc

Poisson survival function

pdtrik

inverse of pdtr with respect to k