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# scipy.special.bdtri

`scipy.special.``bdtri`(k, n, y) = <ufunc 'bdtri'>

  Inverse function to `bdtr` with respect to p.

  Finds the event probability p such that the sum of the terms 0 through k of the binomial probability density is equal to the given cumulative probability y.

  Parameters: | k : array_like Number of successes (float). n : array_like Number of events (float) y : array_like Cumulative probability (probability of k or fewer successes in n events).
  Returns: | p : ndarray The event probability such that bdtr(k, n, p) = y.

  See also

  `bdtr`, `betaincinv`

  Notes

  The computation is carried out using the inverse beta integral function and the relation,:

      1 - p = betaincinv(n - k, k + 1, y).

  Wrapper for the Cephes [R373] routine `bdtri`.

  References

  [R373] | (1, 2) Cephes Mathematical Functions Library, http://www.netlib.org/cephes/index.html