# scipy.special.erf

scipy.special.erf(z) = <ufunc 'erf'>

  Returns the error function of complex argument.

  It is defined as `2/sqrt(pi)*integral(exp(-t**2), t=0..z)`.

  Parameters
    x ndarray

      Input array.

  Returns
    res ndarray

      The values of the error function at the given points x.

  See also

  `erfc`, `erfinv`, `erfcinv`, `wofz`, `erfcx`, `erfi`

  Notes

  The cumulative of the unit normal distribution is given by `Phi(z) = 1/2[1 + erf(z/sqrt(2))]`.

  References

  1

    https://en.wikipedia.org/wiki/Error_function

  2

    Milton Abramowitz and Irene A. Stegun, eds. Handbook of Mathematical Functions with Formulas, Graphs, and Mathematical Tables. New York: Dover, 1972. http://www.math.sfu.ca/~cbm/aands/page_297.htm

  3

    Steven G. Johnson, Faddeeva W function implementation. http://ab-initio.mit.edu/Faddeeva

  Examples

      >>> from scipy import special
      >>> import matplotlib.pyplot as plt
      >>> x = np.linspace(-3, 3)
      >>> plt.plot(x, special.erf(x))
      >>> plt.xlabel('$x$')
      >>> plt.ylabel('$erf(x)$')
      >>> plt.show()

scipy.special.poch scipy.special.erfc