Log normal distribution

The probability density function for log normal distribution is:

.. math::

f(x, s)= \frac{1}{x\sqrt{2\pi}s }\exp\left ( - \frac{(\ln x-\mu )^{2}}{2s ^{2}} \right )

for :math:x>0 and :math:s > 0.

The following plots show the pdf and cdf:

.. image:: ../../../../tests/imgs/stats/continuous/lognormal/lognormalpdf.png :align: center :width: 480

.. image:: ../../../../tests/imgs/stats/continuous/lognormal/lognormalcdf.png :align: center :width: 480