JavaUtilityFunction

class negmas.utilities.JavaUtilityFunction(java_object, java_class_name: Optional[str], *args, **kwargs)[source]

Bases: negmas.utilities.UtilityFunction, negmas.java.JavaCallerMixin

A utility function implemented in Java

Methods Summary

eval(offer)

Calculate the utility value for a given outcome.

xml(issues)

Converts the function into a well formed XML string preferrably in GENIUS format.

Methods Documentation

eval(offer: Union[negmas.outcomes.OutcomeType, Tuple[Union[int, float, str, list]], Dict[Union[int, str], Union[int, float, str, list]]])Union[negmas.helpers.Distribution, float][source]

Calculate the utility value for a given outcome.

Parameters

offer – The offer to be evaluated.

Returns

The utility_function value which may be a distribution.

If None it means the utility_function value cannot be calculated.

Return type

UtilityValue

Remarks:
  • You cannot return None from overriden eval() functions but raise an exception (ValueError) if it was not possible to calculate the UtilityValue.

  • Typehint the return type as a UtilityValue instead of a float for the benefit of inspection code.

  • Return the reserved value if the offer was None

  • NEVER call the baseclass using super() when overriding this method. Calling super will lead to an infinite loop.

  • The default implementation assumes that is_better is defined and uses it to do the evaluation. Note that the default implementation of is_better does assume that eval is defined and uses it. This means that failing to define both leads to an infinite loop.

xml(issues: List[negmas.outcomes.Issue])str[source]

Converts the function into a well formed XML string preferrably in GENIUS format.

If the output has with </objective> then discount factor and reserved value should also be included If the output has </utility_space> it will not be appended in to_xml_str