


Logarithm and Related Functions
===============================

Information on the properties of the Logarithm function can be found
in Abramowitz & Stegun, Chapter 4.

.. index:: logarithm

.. function:: gsl_sf_log(x)

 This routine computes the logarithm of :math:`x`, :math:`\log(x)`, for :math:`x > 0`.

.. function:: gsl_sf_log_abs(x)

 This routine computes the logarithm of the magnitude of :math:`x`,
 :math:`\log(|x|)`, for :math:`x \ne 0`.

.. function:: gsl_sf_log_1plusx(x)

 This routine computes :math:`\log(1 + x)` for :math:`x > -1` using an algorithm
 that is accurate for small :math:`x`.

.. function:: gsl_sf_log_1plusx_mx(x)

 This routine computes :math:`\log(1 + x) - x` for :math:`x > -1` using an
 algorithm that is accurate for small :math:`x`.
