regions.write_crtf(regions, filename, coordsys='fk5', fmt='.6f', radunit='deg')[source]

Converts a list of Region to CRTF string and write to file.

See Reading/writing to CRTF region files

regions : list

List of Region objects

filename : str

Filename in which the string is to be written. Default is ‘new.crtf’

coordsys : str, optional

Astropy Coordinate system that overrides the coordinate frames of all regions. Default is ‘fk5’.

fmt : str, optional

A python string format defining the output precision. Default is .6f, which is accurate to 0.0036 arcseconds.

radunit : str, optional

This denotes the unit of the radius. Default is deg (degrees)