Source Code for Module classifiers.g_class_centers

 1  #!/usr/bin/env python 
 2   
 3  """This computes centers for classes. 
 4  You give it a classified.fiat file on the argument list, 
 5  as obtained from *_classifier.py, and it 
 6  produces a list of files, class names, and the feature vector 
 7  at the center of each class. 
 8   
 9  To define the center, it takes the component-by-component 
10  median of the feature vector, including only 
11  data that are correctly classified. 
12  """ 
13   
14   
15  import math 
16  import gpkavg 
17  from gmisclib import gpkmisc 
18  from gmisclib import Num 
19  from gmisclib import die 
20  from gmisclib import dictops 
21  import q_classifier_r 
22   
23  CLIP = 0.15 
24   
25   
26 -def process(f): 
27          h, data, c = q_classifier_r.read_fiat(open(f, 'r')) 
28          lp = [] 
29          nic = {} 
30          for datum in data: 
31                  if datum['trueclass'] == datum['compclass']: 
32                          lp.append( datum['V'].shape[0] ) 
33                          tc = datum['trueclass'] 
34                          dictops.add_doc(nic, tc, 1) 
35          n = int(math.ceil(gpkmisc.median(lp))) 
36   
37          index = {} 
38          psa = {} 
39          for (cl, nicl) in nic.items(): 
40                  psa[cl] = Num.zeros( (n, nicl), Num.Float) 
41                  index[cl] = 0 
42   
43          for datum in data: 
44                  if datum['trueclass'] == datum['compclass']: 
45                          v = datum['V'] 
46                          ml = min( v.shape[0], n ) 
47                          tc = datum['trueclass'] 
48                          psa[tc][:n,index[tc]] = v[:n] 
49                          index[tc] += 1 
50          o = {} 
51          for cl in nic.keys(): 
52                  acoef = Num.zeros((n,), Num.Float) 
53                  vcoef = Num.zeros((n,), Num.Float) 
54                  for j in range(n): 
55                          thisAvg, thisVar = gpkavg.avg(psa[cl][j,:], None, CLIP) 
56                          acoef[j] = thisAvg 
57                          vcoef[j] = thisVar 
58                  o[cl] = (acoef, vcoef) 
59          return o 
60   
61   
62 -def format(v): 
63          return ' '.join( [ '%f' % x for x in v ] ) 
64   
65   
66  if __name__ == '__main__': 
67          import sys 
68          arglist = sys.argv[1:] 
69          Var = False 
70          while arglist and arglist[0].startswith('-'): 
71                  arg = arglist.pop(0) 
72                  if arg == '--': 
73                          break 
74                  elif arg == '-var': 
75                          Var = True 
76                  elif arg == '-clip': 
77                          CLIP = float(arglist.pop(0)) 
78                  else: 
79                          die.die('Unrecognized flag: %s' % arg) 
80   
81          for f in arglist: 
82                  typ = process(f) 
83                  for (cl, (acoef, vcoef)) in typ.items(): 
84                          if Var: 
85                                  print f, cl, format(vcoef) 
86                          else: 
87                                  print f, cl, format(acoef) 
88