:py:mod:`gnome.utilities.rand`
==============================

.. py:module:: gnome.utilities.rand

.. autoapi-nested-parse::

   rand.py

   Contains functions for adding randomness - not to
   confuse with standard python random functions



Module Contents
---------------


Functions
~~~~~~~~~

.. autoapisummary::

   gnome.utilities.rand.random_with_persistance
   gnome.utilities.rand.seed



.. py:function:: random_with_persistance(low, high, array=None, persistence=None, time_step=1.0)

   Used by gnome to generate a randomness between low and high, which is
   persistent for duration time_step

   :param low: lower bound for random number; should be an array, tuple, list
   :param high: upper bound for random number; should be an array, tuple, list
   :param array: array to be updated. Must be same length as 'low', 'high',
       'persistence'. Default is None in which case the computed array is
       simply returned
   :param time_step: step size for the simulation in seconds.
   :param persistence: in seconds. Since we add randomness for each timestep,
       the persistence parameter is used to make the randomness invariant to
       size of time_step. Default is None. If persistence is None, it gets set
       equal to 'time_step'. If persistence < 0 for any elements, their values
       are not updated in the 'array'

   :returns: returns 'array' with newly computed values

   Note: persistence and time_step should be in the same time units
         Assumes both low and high are int/float or arrays, lists, tuples.
         For lists, arrays, tuples - it converts input to numpy array with
         dtype=float

         If 'low' is an array, list or tuple, then 'high' and 'persistence'
         should also be the same length array, list or tuple. Give
         all 3 parameters for each element of the array.


.. py:function:: seed(seed=1)

   Set the C++, the python and the numpy random seed to desired value

   :param seed: Random number generator should be seeded by this value.
       Default is 1