error parsing regions with dimensions in degrees, radians, physical/image pixels

I created this in the aplpy site (https://github.com/aplpy/aplpy/issues/381) but it seems it may be more relevant here.

using aplpy.FITSFigure.show_regions I can load a region file with the following content just fine:

fk5
circle(10.0,-5.0,10")

but when the units correspond to a letter (i.e., 'd' for degrees, 'r' for radians, 'p' for physical pixels or 'i' for image pixels), the command cannot be parsed. Take a file with the following content

fk5
circle(10.0,-5.0,0.02d)

This file loads without a problem in ds9, but when passed to aplpy.FITSFigure.show_regions it issues the following warning:

/Users/cristobal/anaconda3/lib/python3.6/site-packages/pyregion/ds9_region_parser.py:107: UserWarning: Failed to parse : circle(10.0,-5.0,0.02d)

If this happens with all the entries in my reg file, then the following exception is raised:

---------------------------------------------------------------------------
ValueError                                Traceback (most recent call last)
<ipython-input-9-e910de502d80> in <module>()
      6 regfile = mask.regions()
      7 #img.show_regions(regfile)
----> 8 img.show_regions('test.reg')

/Users/cristobal/anaconda3/envs/pyraf/lib/python2.7/site-packages/aplpy/regions.pyc in show_regions(self, region_file, layer, **kwargs)

/Users/cristobal/anaconda3/envs/pyraf/lib/python2.7/site-packages/aplpy/decorators.pyc in _auto_refresh(f, *args, **kwargs)
     23     mydata.nesting = getattr(mydata, 'nesting', 0) + 1
     24     try:
---> 25         return f(*args, **kwargs)
     26     finally:
     27         mydata.nesting -= 1

/Users/cristobal/anaconda3/envs/pyraf/lib/python2.7/site-packages/aplpy/regions.pyc in show_regions(self, region_file, layer, **kwargs)
     63         """
     64 
---> 65         PC, TC = ds9(region_file, wcs.WCS(self._header).sub([wcs.WCSSUB_CELESTIAL]), **kwargs)
     66 
     67         # ffpc = self._ax1.add_collection(PC)

/Users/cristobal/anaconda3/envs/pyraf/lib/python2.7/site-packages/aplpy/regions.pyc in ds9(region_file, header, zorder, **kwargs)
     94     # read region file
     95     if isinstance(region_file, six.string_types):
---> 96         rr = pyregion.open(region_file)
     97     elif isinstance(region_file, pyregion.ShapeList):
     98         rr = region_file

/Users/cristobal/anaconda3/envs/pyraf/lib/python2.7/site-packages/pyregion/core.pyc in open(fname)
    264     """
    265     region_string = _builtin_open(fname).read()
--> 266     return parse(region_string)
    267 
    268 

/Users/cristobal/anaconda3/envs/pyraf/lib/python2.7/site-packages/pyregion/core.pyc in parse(region_string)
    246     sss2 = _check_wcs(sss1)
    247 
--> 248     shape_list, comment_list = rp.filter_shape2(sss2)
    249     return ShapeList(shape_list, comment_list=comment_list)
    250 

ValueError: need more than 0 values to unpack

N.B. all this is with pyregion 1.2.0 re: https://github.com/aplpy/aplpy/issues/369

astropy / pyregion

error parsing regions with dimensions in degrees, radians, physical/image pixels #127