make the visitreader to work with any dumpreader

The Visitreader stores the information about the dumpreader class that
should be used to read the dumps. This will allow to read full
Simulations via visitfiles written by different codes simultaneously.

postpic/datareader/__init__.py

@@ -221,12 +221,12 @@ def __getitem__(self, key):
                 key += len(self)
             if key >= len(self):
                 raise IndexError("The index (%d) is out of range." % key)
-            return self.getDumpnumber(key)
+            return self.getDumpreader(key)
         else:
             raise TypeError("Invalid argument type.")
 
     @abc.abstractmethod
-    def getDumpnumber(self, number):
+    def getDumpreader(self, number):
         '''
         :returns: the corresponding Dumpreader.
         '''

postpic/datareader/dummy.py

@@ -160,7 +160,7 @@ def __init__(self, simidentifier, dimensions=2, **kwargs):
     def __len__(self):
         return self.simidentifier
 
-    def getDumpnumber(self, index):
+    def getDumpreader(self, index):
         if index < len(self):
             return Dummyreader(index, dimensions=self._dimensions)
         else:

postpic/datareader/epochsdf.py

@@ -145,9 +145,10 @@ class Visitreader(Simulationreader_ifc):
     any other code using these files.
     '''
 
-    def __init__(self, visitfile, **kwargs):
+    def __init__(self, visitfile, dumpreadercls=Sdfreader, **kwargs):
         super(self.__class__, self).__init__(visitfile, **kwargs)
         self.visitfile = visitfile
+        self.dumpreadercls = dumpreadercls
         import os.path
         if not os.path.isfile(visitfile):
             raise IOError('File "' + str(visitfile) + '" doesnt exist.')
@@ -161,9 +162,8 @@ def __init__(self, visitfile, **kwargs):
     def __len__(self):
         return len(self._dumpfiles)
 
-    def getDumpnumber(self, index):
-        from . import readDump
-        return readDump(self._dumpfiles[index])
+    def getDumpreader(self, index):
+        return self.dumpreadercls(self._dumpfiles[index])
 
     def __str__(self):
         return '<Visitreader at "' + self.visitfile + '">'