Source code for magni.cs.reconstruction.sl0._L_update
"""
..
Copyright (c) 2015-2017, Magni developers.
All rights reserved.
See LICENSE.rst for further information.
Module providing functions for calculating the updated value of L (the number
of gradient descent iterations for each sigma) used in the Smoothed l0
algorithms.
Routine listings
----------------
calculate_using_fixed(var)
Calculate the updated, fixed L value.
calculate_using_geometric(var)
Calculate an updated L value in a 'geometric' way.
get_function_handle(method)
Return a function handle to a given calculation method.
"""
from __future__ import division
[docs]def wrap_calculate_using_fixed(var):
"""
Arguments wrapper for calculate_using_fixed.
"""
convert = var['convert']
L = convert(var['param']['L_fixed'])
def calculate_using_fixed(var):
"""
Calculate the updated, fixed L value.
Parameters
----------
var : dict
Dictionary of variables used in the calculation of the updated L
value.
Returns
-------
L : float
The updated L value to be used in the SL0 algorithm.
"""
return L
return calculate_using_fixed
[docs]def wrap_calculate_using_geometric(var):
"""
Arguments wrapper for calculate_using_geometric.
"""
convert = var['convert']
L_ratio = convert(var['param']['L_geometric_ratio'])
def calculate_using_geometric(var):
"""
Calculate an updated L value in a 'geometric' way.
Parameters
----------
var : dict
Dictionary of variables used in the calculation of the updated L
value.
Returns
-------
L : float
The updated L value to be used in the SL0 algorithm.
"""
return L_ratio * var['L']
return calculate_using_geometric
[docs]def get_function_handle(method, var):
"""
Return a function handle to a given calculation method.
Parameters
----------
method : str
Identifier of the calculation method to return a handle to.
var : dict
Local variables needed in the L update method.
Returns
-------
f_handle : function
Handle to the calculation method defined in this globals scope.
"""
return globals()['wrap_calculate_using_' + method](var)