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# scipy.special.log1p

scipy.special.log1p(x, out=None) = <ufunc 'log1p'>

  Calculates log(1 + x) for use when x is near zero.

  Parameters:
    xarray_like

      Real or complex valued input.

    outndarray, optional

      Optional output array for the function results.

  Returns:
    scalar or ndarray

      Values of `log(1 + x)`.

  See also

  `expm1`, `cosm1`

  Examples

      >>> import numpy as np
      >>> import scipy.special as sc

  It is more accurate than using `log(1 + x)` directly for `x` near 0. Note that in the below example `1 + 1e-17 == 1` to double precision.

      >>> sc.log1p(1e-17)
      1e-17
      >>> np.log(1 + 1e-17)
      0.0