def getDataMap(self, intype, pos, name, offset = 0):
        """
        Hook defined to lookup a name, and get it from a vector.
        Can be overloaded to get it from somewhere else.
        """
        if intype == "input":
            vector = self.inputs
        elif intype == "target":
            vector = self.targets
        else:
            raise AttributeError("invalid map type '%s'" % intype)
        return vector[pos][offset:offset+self[name].size]