


The Laplace Distribution
========================

.. function:: gsl_ran_laplace(a)

 This function returns a random variate from the :index:`Laplace
 distribution` with width ``a``. The distribution is,

 .. math::
   p(x) dx = {1 \over 2 a}  \exp(-|x/a|) dx

 for :math:`-\infty < x < \infty`.

.. function:: gsl_ran_laplace_pdf(x, a)

 This function computes the probability density :math:`p(x)` at :math:`x` for a
 Laplace distribution with width ``a``, using the formula given above.

.. function:: gsl_ran_laplace_P(x, a)

.. function:: gsl_ran_laplace_Q(x, a)

.. function:: gsl_ran_laplace_Pinv(P, a)

.. function:: gsl_ran_laplace_Qinv(Q, a)

 These functions compute the cumulative distribution functions
 :math:`P(x), Q(x)` and their inverses for the Laplace distribution
 with width ``a``.
