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# scipy.special.boxcox1p

`scipy.special.``boxcox1p`(x, lmbda) = <ufunc 'boxcox1p'>

  Compute the Box-Cox transformation of 1 + x.

  The Box-Cox transformation computed by `boxcox1p` is:

      y = ((1+x)**lmbda - 1) / lmbda  if lmbda != 0
          log(1+x)                    if lmbda == 0

  Returns nan if `x < -1`. Returns -inf if `x == -1` and `lmbda < 0`.

  Parameters: | x : array_like Data to be transformed. lmbda : array_like Power parameter of the Box-Cox transform.
  Returns: | y : array Transformed data.

  Notes

  New in version 0.14.0.

  Examples

      >>> boxcox1p(1e-4, [0, 0.5, 1])
      array([  9.99950003e-05,   9.99975001e-05,   1.00000000e-04])
      >>> boxcox1p([0.01, 0.1], 0.25)
      array([ 0.00996272,  0.09645476])