xarray_polyfit_eval

PlasmaCalcs.tools.xarray_tools.xarray_sci.xarray_polyfit_eval(dataset, at=None, *, to_dataset=False)

evaluate the polyfit in dataset at these coordinates.

E.g. dataset has degree=2,1,0, polyfit_coefficients=7.5, -3.2, 0.4
–> result == 7.5 * at**2 - 3.2 * at + 0.4
if input dataset contains ‘polyfit_stddev’, instead returns a dataset with:
‘polyfit_eval’: result (see above)
‘polyfit_eval-stddev’: result when using polyfit_coefficients - polyfit_stddev.
‘polyfit_eval+stddev’: result when using polyfit_coefficients + polyfit_stddev.
at: None or array
if provided, evaluate polyfit dataset here.
None –> input MUST be a dataset which already has ‘polyfit_eval’;
instead of computing terms, just return relevant info which exists in dataset,
i.e. ‘polyfit_eval’, ‘polyfit_eval-stddev’, and/or ‘polyfit_eval+stddev’.
to_dataset: bool
whether to return dataset even if input does not contain ‘polyfit_stddev’
True –> result will always be a dataset.