.. _method-optpp_g_newton-merit_function-van_shanno:

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van_shanno
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The merit function by Vanderbei and Shanno


.. toctree::
   :hidden:
   :maxdepth: 1



**Specification**

- *Alias:* None

- *Arguments:* None


**Description**


The "van_shanno" merit function can be classified as a penalty
function for the logarithmic barrier formulation of the nonlinear
programming problem. The cost per linesearch iteration is one function
evaluation. For more information see :cite:p:`VanShanno1999`.

If the function evaluation is expensive or noisy, set the
``merit_function`` to "argaez_tapia" or "van_shanno".


