Code does not pass WMM validation.

[jzampieron]

Hi... was working with this code base and discovered that you don't run any unit tests again the NOAA provided WMM Test Data.

When I wrote tests to use that data your code doesn't match with the reference values.

I've since deleted all our use of this code base and re-implemented against the C code directly.

Here's the reference code: https://www.ncei.noaa.gov/magnetic-model-survey-page?redirect=software-coefficients-linux

Your values work for some points and can be close (with 0.5 deg or so) for others.

Recommend you pull this code or fix it because right now the performance and quality here is unacceptable for most uses.