On Tue, Apr 25, 2017 at 7:52 PM Phil Hodge <hodge@stsci.edu> wrote:

On 04/25/2017 01:34 PM, Anne Archibald wrote:
> I know they're not numpy-compatible, but FITS header values are
> space-padded; does that occur elsewhere?

Strings in FITS headers are delimited by single quotes. Some keywords
(only a handful) are required to have values that are blank-padded (in
the FITS file) if the value is less than eight characters. Whether you
get trailing blanks when you read the header depends on the FITS
reader. I use astropy.io.fits to read/write FITS files, and that
interface strips trailing blanks from character strings:

TARGPROP= 'UNKNOWN ' / Proposer's name for the target

>>> fd = fits.open("test.fits")
>>> s = fd[0].header['targprop']
>>> len(s)
7

Actually, for what it's worth, the FITS spec says that in such values trailing spaces are not significant, see page 7:

https://fits.gsfc.nasa.gov/standard40/fits_standard40draft1.pdf

But they're not really relevant to numpy's situation, because as here you need to do elaborate de-quoting before they can go into a data structure. What I was wondering was whether people have data lying around with fixed-width fields where the strings are space-padded, so that numpy needs to support that.

Anne