gnome.utilities.rand

rand.py

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

Module Contents

Functions

random_with_persistance(low, high[, array, ...])

Used by gnome to generate a randomness between low and high, which is

seed([seed])

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

gnome.utilities.rand.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

Parameters:
  • low – lower bound for random number; should be an array, tuple, list

  • high – upper bound for random number; should be an array, tuple, list

  • 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

  • time_step – step size for the simulation in seconds.

  • 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.

gnome.utilities.rand.seed(seed=1)

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

Parameters:

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