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# scipy.special.chndtrinc

scipy.special.chndtrinc(x, df, p, out=None) = <ufunc 'chndtrinc'>

  Inverse of `chndtr` with respect to nc.

  Finds the non-centrality parameter nc such that

  \[\operatorname{chndtr}(x, df, nc) = p.\]
  Parameters:
    x array_like

      Upper bound of the integral; must satisfy `x >= 0`.

    df array_like

      Degrees of freedom; must satisfy `df > 0`.

    p array_like

      Probability; must satisfy `0 <= p < 1`.

    out ndarray, optional

      Optional output array for the function results.

  Returns:
    nc scalar or ndarray

      Non-centrality parameter.

  See also

  `chndtr`

    Noncentral chi-squared distribution CDF

  `chndtridf`

    Inverse of `chndtr` with respect to df

  `chndtrinc`

    Inverse of `chndtr` with respect to nc

  `scipy.stats.ncx2`

    Non-central chi-squared distribution

  Notes

  The noncentral chi squared distribution is also available in `scipy.stats.ncx2`.

  This function wraps routines from the Boost Math C++ library [1].

  References

  [1]

  The Boost Developers. “Boost C++ Libraries”. https://www.boost.org/.

  Examples

      >>> from scipy.special import chndtrinc, chndtr

  Compute the noncentral chi squared distribution CDF at one point.

      >>> x, df, nc = 3, 5, 10
      >>> p = chndtr(x, df, nc)

  `chndtrinc` is the inverse of `chndtr` with respect to nc:

      >>> chndtrinc(x, df, p)
      10.0