scipy.special.nctdtridf — SciPy v1.15.3 Manual (original) (raw)

scipy.special.nctdtridf(p, nc, t, out=None) = <ufunc 'nctdtridf'>#

Calculate degrees of freedom for non-central t distribution.

See nctdtr for more details.

Parameters:

parray_like

CDF values, in range (0, 1].

ncarray_like

Noncentrality parameter. Should be in range (-1e6, 1e6).

tarray_like

Quantiles, i.e., the upper limit of integration.

outndarray, optional

Optional output array for the function results

Returns:

dfscalar or ndarray

The degrees of freedom. If all inputs are scalar, the return will be a float. Otherwise, it will be an array.

See also

nctdtr

CDF of the non-central t distribution.

nctdtrit

Inverse CDF (iCDF) of the non-central t distribution.

nctdtrinc

Calculate non-centrality parameter, given CDF iCDF values.

Examples

from scipy.special import nctdtr, nctdtridf

Compute the CDF for several values of df:

df = [1, 2, 3] p = nctdtr(df, 0.25, 1) p array([0.67491974, 0.716464 , 0.73349456])

Compute the inverse. We recover the values of df, as expected:

nctdtridf(p, 0.25, 1) array([1., 2., 3.])