Source Code for Module parsimony.algorithms.deflation

 1  # -*- coding: utf-8 -*- 
 2  """ 
 3  The :mod:`parsimony.algorithms.deflation` module contains deflation procedures. 
 4  functions. 
 5   
 6  Created on Fri Mar 21 15:18:56 2014 
 7   
 8  Copyright (c) 2013-2014, CEA/DSV/I2BM/Neurospin. All rights reserved. 
 9   
10  @author:  Tommy Löfstedt 
11  @email:   lofstedt.tommy@gmail.com 
12  @license: BSD 3-clause. 
13  """ 
14  import abc 
15   
16  import numpy as np 
17   
18  __all__ = ["ProjectionDeflation", 
19             "RowProjectionDeflation", "ColumnProjectionDeflation", 
20             "RankOneDeflation"] 
21   
22   
23 -class Deflation(object): 
24      __metaclass__ = abc.ABCMeta 
25   
26      @abc.abstractmethod 
27 -    def deflate(self, X, w): 
28          raise NotImplementedError('Abstract method "deflate" must be ' \ 
29                                    'specialised!') 
30   
31   
32 -class RowProjectionDeflation(Deflation): 
33   
34 -    def deflate(self, X, w): 
35          return X - np.dot(np.dot(X, w), w.T) / np.dot(w.T, w) 
36   
37   
38  ProjectionDeflation = RowProjectionDeflation 
39   
40   
41 -class ColumnProjectionDeflation(Deflation): 
42   
43 -    def deflate(self, X, t): 
44          return X - np.dot(t / np.dot(t.T, t), np.dot(t.T, X)) 
45   
46   
47 -class RankOneDeflation(Deflation): 
48   
49 -    def deflate(self, X, t, p): 
50          return X - np.dot(t, p.T) 
51