.. _fast_newuoa:

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fast_newuoa
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.. tags:: astero, optimization, newuoa, synthetic-data, chi-squared, custom-variables, solar-calibration, low-mass, element-diffusion

Runs first few steps of a NEWUOA optimisation for some synthetic data.
This test exists only to increase test coverage of the routines
involved in a NEWUOA optimisation (some of which is used by other
optimisation routines).  It should not be the basis of any scientific
runs.  The tolerances are all very loose to make each iteration fast
enough that the test completes within a few minutes.  The data is taken from
the output of a 1 |Msun| model at an age around 1 Gyr.

To increase coverage, this test uses the custom variables implemented
in ``my_var1``, ``my_var2`` and ``my_var3``.  Specifically, it sets
these to the luminosity, effective temperature and radius of the Sun.
It also sets ``chi2_seismo_fraction`` to zero, so the test mimics a
traditional solar calibration.  It almost certainly won't converge,
however, because NEWUOA is prone to rapidly getting stuck in local
minima.

The output in effect only checks that at least one set of trial
parameters returned a value of |chi^2|.  There are two main failure
modes.  First, failure might benignly indicate that the initial
parameters have strayed too far from the synthetic constraints to
produce any output, in which case the initial guesses or target data
should be adjusted.  Second, failure might indicate that the NEWUOA
optimisation is genuinely broken and needs fixing.

Last-Update: 2022-03-29 (mesa 998d243) by Warrick Ball