Source Code for Module mvpa.misc.param

  1  #emacs: -*- mode: python-mode; py-indent-offset: 4; indent-tabs-mode: nil -*- 
  2  #ex: set sts=4 ts=4 sw=4 et: 
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  4  # 
  5  #   See COPYING file distributed along with the PyMVPA package for the 
  6  #   copyright and license terms. 
  7  # 
  8  ### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ##g 
  9  """Parameter representation""" 
 10   
 11  __docformat__ = 'restructuredtext' 
 12   
 13  import textwrap 
 14  from mvpa.misc.state import CollectableAttribute 
 15   
 16  if __debug__: 
 17      from mvpa.base import debug 
 18   
 19 -class Parameter(CollectableAttribute): 
 20      """This class shall serve as a representation of a parameter. 
 21   
 22      It might be useful if a little more information than the pure parameter 
 23      value is required (or even only useful). 
 24   
 25      Each parameter must have a value. However additional property can be 
 26      passed to the constructor and will be stored in the object. 
 27   
 28      BIG ASSUMPTION: stored values are not mutable, ie nobody should do 
 29   
 30      cls.parameter1[:] = ... 
 31   
 32      or we wouldn't know that it was changed 
 33   
 34      Here is a list of possible property names: 
 35   
 36          min   - minimum value 
 37          max   - maximum value 
 38          step  - increment/decrement stepsize 
 39      """ 
 40   
 41 -    def __init__(self, default, name=None, doc=None, index=None, **kwargs): 
 42          """Specify a parameter by its default value and optionally an arbitrary 
 43          number of additional parameters. 
 44   
 45          TODO: :Parameters: for Parameter 
 46          """ 
 47          self.__default = default 
 48   
 49          CollectableAttribute.__init__(self, name=name, doc=doc, index=index) 
 50   
 51          self.resetvalue() 
 52          self._isset = False 
 53   
 54          if __debug__: 
 55              if kwargs.has_key('val'): 
 56                  raise ValueError, "'val' property name is illegal." 
 57   
 58          # XXX probably is too generic... 
 59          for k, v in kwargs.iteritems(): 
 60              self.__setattr__(k, v) 
 61   
 62   
 63 -    def __str__(self): 
 64          res = CollectableAttribute.__str__(self) 
 65          # it is enabled but no value is assigned yet 
 66          res += '=%s' % (self.value,) 
 67          return res 
 68   
 69   
 70 -    def doc(self, indent="  ", width=70): 
 71          """Docstring for the parameter to be used in lists of parameters 
 72   
 73          :Returns: 
 74            string or list of strings (if indent is None) 
 75          """ 
 76          paramsdoc = "  %s" % self.name 
 77          if hasattr(paramsdoc, 'allowedtype'): 
 78              paramsdoc += " : %s" % self.allowedtype 
 79          paramsdoc = [paramsdoc] 
 80          try: 
 81              doc = self.__doc__ 
 82              if not doc.endswith('.'): doc += '.' 
 83              try: 
 84                  doc += " (Default: %s)" % self.default 
 85              except: 
 86                  pass 
 87              paramsdoc += ['  ' + x 
 88                            for x in textwrap.wrap(doc, width=width-len(indent))] 
 89          except Exception, e: 
 90              pass 
 91   
 92          if indent is None: 
 93              return paramsdoc 
 94          else: 
 95              return ('\n' + indent).join(paramsdoc) 
 96   
 97   
 98      # XXX should be named reset2default? correspondingly in 
 99      #     ParameterCollection as well 
100 -    def resetvalue(self): 
101          """Reset value to the default""" 
102          #CollectableAttribute.reset(self) 
103          if not self.isDefault: 
104              self._isset = True 
105              self.value = self.__default 
106   
107 -    def _set(self, val): 
108          if self._value != val: 
109              if __debug__: 
110                  debug("COL", 
111                        "Parameter: setting %s to %s " % (str(self), val)) 
112              if hasattr(self, 'min') and val < self.min: 
113                  raise ValueError, \ 
114                        "Minimal value for parameter %s is %s. Got %s" % \ 
115                        (self.name, self.min, val) 
116              if hasattr(self, 'max') and val > self.max: 
117                  raise ValueError, \ 
118                        "Maximal value for parameter %s is %s. Got %s" % \ 
119                        (self.name, self.max, val) 
120              if hasattr(self, 'choices') and (not val in self.choices): 
121                  raise ValueError, \ 
122                        "Valid choices for parameter %s are %s. Got %s" % \ 
123                        (self.name, self.choices, val) 
124              self._value = val 
125              self._isset = True 
126          elif __debug__: 
127              debug("COL", 
128                    "Parameter: not setting %s since value is the same" \ 
129                    % (str(self))) 
130   
131      @property 
132 -    def isDefault(self): 
133          """Returns True if current value is bound to default one""" 
134          return self._value is self.default 
135   
136      @property 
137 -    def equalDefault(self): 
138          """Returns True if current value is equal to default one""" 
139          return self._value == self.__default 
140   
141 -    def setDefault(self, value): 
142          wasdefault = self.isDefault 
143          self.__default = value 
144          if wasdefault: 
145              self.resetvalue() 
146              self._isset = False 
147   
148      # incorrect behavior 
149      #def reset(self): 
150      #    """Override reset so we don't clean the flag""" 
151      #    pass 
152   
153      default = property(fget=lambda x:x.__default, fset=setDefault) 
154      value = property(fget=lambda x:x._value, fset=_set) 
155   
156 -class KernelParameter(Parameter): 
157      """Just that it is different beast""" 
158      pass 
159