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# numpy.expm1

`numpy.``expm1`(x[, out])

  Return the exponential of the elements in the array minus one.

  Parameters: | x : array_like Input values.
  Returns: | out : ndarray Element-wise exponential minus one: `out=exp(x)-1`.

  See also

  `log1p`
    `log(1+x)`, the inverse of expm1.

  Notes

  This function provides greater precision than using `exp(x)-1` for small values of x.

  Examples

  Since the series expansion of `e**x = 1 + x + x**2/2! + x**3/3! + ...`, for very small x we expect that `e**x -1 ~ x + x**2/2`:

      >>> np.expm1(1e-10)
      1.00000000005e-10
      >>> np.exp(1e-10) - 1
      1.000000082740371e-10

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