.. _combinations-doc:

.. ipython:: python
   :suppress:

   from rateslib.instruments import *
   from datetime import datetime as dt

**************************************
Utilities and Instrument Combinations
**************************************

Combinations allow common interbank traded structures to be
created, and :class:`~rateslib.instruments.Value` and :class:`~rateslib.instruments.VolValue` are
null objects typically used to directly parametrize a :ref:`Curve<curves-doc>` or
a :ref:`FXDeltaVolSmile<c-fx-smile-doc>` via a
:class:`~rateslib.solver.Solver`.

.. inheritance-diagram:: rateslib.instruments.Fly rateslib.instruments.Spread rateslib.instruments.Value rateslib.instruments.VolValue  rateslib.instruments.Portfolio
   :private-bases:
   :parts: 1

.. autosummary::
   rateslib.instruments.Value
   rateslib.instruments.VolValue
   rateslib.instruments.Spread
   rateslib.instruments.Fly
   rateslib.instruments.Portfolio