unit_conversion.py¶
Functions for checking and sanitizing units that do not follow the FITS specification.
This uses functions from astropy.unit
to parse and handle units.
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exception
fits2hdf.unit_conversion.
UnitWarning
¶ Bases:
astropy.io.fits.verify.VerifyWarning
Unit warning class
Used when units do not parse or parse oddly
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fits2hdf.unit_conversion.
fits_to_units
(unit_str)¶ Do a lookup from a astropy unit and return a fits unit string
unit_str (str): a FITS unit string returns an astropy.units.Unit(), or UnrecognizedUnit()
This will attempt to correct some common mistakes in the FITS format.
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fits2hdf.unit_conversion.
units_to_fits
(unit)¶ Convert an astropy unit to a FITS format string.
uses the to_string() method built-in to astropy Unit()
The output will be the format defined in the FITS standard: http://fits.gsfc.nasa.gov/fits_standard.html
A roundtrip from fits_to_units -> units_to_fits may not return the original string, as people often don’t follow the standard.