compatibility astropy

[nfbouche]

for unit=u.Unit('nanomaggy'), the line

fits.py:170 dsthdr['BUNIT'] = (unit.to_string('fits'), 'data unit type')

failes inside a try/except.

fix is replacing line fits.py:171 by
except:
instead of
except u.format.fits.UnitScaleError:

[nfbouche]

File ~/.local/lib/python3.9/site-packages/mpdaf/obj/data.py:412, in DataArray.getstate(self)
407 # Try to determine if the object has some wcs/wave information but not
408 # available in the FITS header. In this case we add the wcs info in the
409 # data header.
410 if ((self._has_wcs and self.wcs is not None) or
411 (self._has_wave and self.wave is not None)):
--> 412 hdu = self.get_data_hdu(convert_float32=False)
413 state['data_header'] = hdu.header
415 return state

File ~/.local/lib/python3.9/site-packages/mpdaf/obj/data.py:1070, in DataArray.get_data_hdu(self, name, savemask, convert_float32)
1067 else:
1068 data = data.data
-> 1070 hdr = copy_header(self.data_header, self.get_wcs_header(),
1071 exclude=('CD*', 'PC*', 'CDELT*', 'CRPIX*', 'CRVAL*',
1072 'CSYER*', 'CTYPE*', 'CUNIT*', 'NAXIS*',
1073 'RADESYS', 'LATPOLE', 'LONPOLE'),
1074 unit=self.unit)
1075 return fits.ImageHDU(name=name, data=data, header=hdr)

File ~/.local/lib/python3.9/site-packages/mpdaf/tools/fits.py:170, in copy_header(srchdr, dsthdr, exclude, unit)
168 if unit is not None:
169 try:
--> 170 dsthdr['BUNIT'] = (unit.to_string('fits'), 'data unit type')
171 except u.format.fits.UnitScaleError:
172 dsthdr['BUNIT'] = (fix_unit_write(str(unit)), 'data unit type')

File ~/Python/anaconda3/envs/musex/lib/python3.9/site-packages/astropy/units/core.py:791, in UnitBase.to_string(self, format, **kwargs)
749 r"""Output the unit in the given format as a string.
750
751 Parameters
(...)
788 s
789 """
790 f = unit_format.get_format(format)
--> 791 return f.to_string(self, **kwargs)

File ~/Python/anaconda3/envs/musex/lib/python3.9/site-packages/astropy/units/format/fits.py:111, in Fits.to_string(cls, unit, fraction)
108 @classmethod
109 def to_string(cls, unit, fraction=False):
110 # Remove units that aren't known to the format
--> 111 unit = utils.decompose_to_known_units(unit, cls._get_unit_name)
113 parts = []
115 base = np.log10(unit.scale)

File ~/Python/anaconda3/envs/musex/lib/python3.9/site-packages/astropy/units/format/utils.py:109, in decompose_to_known_units(unit, func)
107 except ValueError:
108 if isinstance(unit, core.Unit):
--> 109 return decompose_to_known_units(unit._represents, func)
110 raise
111 return unit

File ~/Python/anaconda3/envs/musex/lib/python3.9/site-packages/astropy/units/format/utils.py:102, in decompose_to_known_units(unit, func)
100 new_unit = core.Unit(unit.scale)
101 for base, power in zip(unit.bases, unit.powers):
--> 102 new_unit = new_unit * decompose_to_known_units(base, func) ** power
103 return new_unit
104 elif isinstance(unit, core.NamedUnit):

File ~/Python/anaconda3/envs/musex/lib/python3.9/site-packages/astropy/units/format/utils.py:106, in decompose_to_known_units(unit, func)
104 elif isinstance(unit, core.NamedUnit):
105 try:
--> 106 func(unit)
107 except ValueError:
108 if isinstance(unit, core.Unit):

File ~/Python/anaconda3/envs/musex/lib/python3.9/site-packages/astropy/units/format/fits.py:105, in Fits._get_unit_name(cls, unit)
102 @classmethod
103 def _get_unit_name(cls, unit):
104 name = super()._get_unit_name(unit)
--> 105 cls._validate_unit(name)
106 return name

File ~/Python/anaconda3/envs/musex/lib/python3.9/site-packages/astropy/units/format/fits.py:80, in Fits._validate_unit(cls, unit, detailed_exception)
78 if unit not in cls._units:
79 if detailed_exception:
---> 80 raise ValueError(
81 f"Unit '{unit}' not supported by the FITS standard. "
82 + utils.did_you_mean_units(
83 unit,
84 cls._units,
85 cls._deprecated_units,
86 cls._to_decomposed_alternative,
87 ),
88 )
89 else:
90 raise ValueError()

ValueError: Unit 'mgy' not supported by the FITS standard. Did you mean MG, Mg, mG or mg?