Package parsimony :: Package functions :: Module penalties :: Class ZeroFunction

Class ZeroFunction

               object --+        
                        |        
      properties.Function --+    
                            |    
    properties.AtomicFunction --+
                                |
                   object --+   |
                            |   |
          properties.Gradient --+
                                |
                   object --+   |
                            |   |
           properties.Penalty --+
                                |
                   object --+   |
                            |   |
        properties.Constraint --+
                                |
                   object --+   |
                            |   |
  properties.ProximalOperator --+
                                |
                   object --+   |
                            |   |
properties.ProjectionOperator --+
                                |
                               ZeroFunction

Instance Methods

[hide private]

__init__(self, l=1.0, c=0.0, penalty_start=0)
Parameters ---------- l : Non-negative float.

source code

reset(self)
Free any cached computations from previous use of this Function.

source code

f(self, x)
Function value.

source code

grad(self, x)
Gradient of the function.

source code

prox(self, x, factor=1.0, **kwargs)
The corresponding proximal operator.

source code

proj(self, x)
The corresponding projection operator.

source code

feasible(self, x)
Feasibility of the constraint.

source code

Inherited from properties.Function: get_params, set_params

Inherited from properties.Gradient: approx_grad

Inherited from object: __delattr__, __format__, __getattribute__, __hash__, __new__, __reduce__, __reduce_ex__, __repr__, __setattr__, __sizeof__, __str__, __subclasshook__

Class Variables

[hide private]

__abstractmethods__ = frozenset([])

Inherited from properties.AtomicFunction: __metaclass__

Inherited from properties.Function (private): _abc_cache, _abc_negative_cache, _abc_negative_cache_version, _abc_registry

Properties

[hide private]

Inherited from object: __class__

Method Details

[hide private]

init(self, l=1.0, c=0.0, penalty_start=0)
(Constructor)

source code


Parameters
----------
l : Non-negative float. The Lagrange multiplier, or regularisation
        constant, of the function.

c : Float. The limit of the constraint. The function is feasible if
        ||eta||_1 <= c. The default value is c=0, i.e. the default is
        a regularisation formulation.

penalty_start : Non-negative integer. The number of columns, variables
        etc., to be exempt from penalisation. Equivalently, the first
        index to be penalised. Default is 0, all columns are included.