def _write_hpx_fits(pixlist):
"""from files that touch a pixel, write out objects in each pixel"""
pixnum, files = pixlist
# ADM only proceed if some files touch a pixel.
if len(files) > 0:
# ADM track if it's our first time through the files loop.
first = True
# ADM Read in files that touch a pixel.
for file in files:
filename = os.path.join(fitsdir, file)
objs = fitsio.read(filename)
# ADM only retain objects in the correct pixel.
pix = radec2pix(nside, objs["RA"], objs["DEC"])
if first:
done = objs[pix == pixnum]
first = False
else:
done = np.hstack([done, objs[pix == pixnum]])
# ADM construct the name of the output file.
outfilename = io.hpx_filename(pixnum)
outfile = os.path.join(hpxdir, outfilename)
# ADM write out the file.
hdr = fitsio.FITSHDR()
hdr['HPXNSIDE'] = nside
hdr['HPXNEST'] = True
fitsio.write(outfile, done, extname='GAIAHPX', header=hdr)
return
def find_gaia_files_tiles(tiles=None, neighbors=True):
"""
Parameters
----------
tiles : :class:`~numpy.ndarray`
Array of tiles, or ``None`` to use all DESI tiles from
:func:`desimodel.io.load_tiles`.
neighbors : :class:`bool`, optional, defaults to ``True``
Also return all neighboring pixels that touch the files of interest
in order to prevent edge effects (e.g. if a Gaia source is 1 arcsec
away from a primary source and so in an adjacent pixel).
Returns
-------
:class:`list`
A list of all Gaia files that touch the passed tiles.
Notes
-----
- The environment variables $GAIA_DIR and $DESIMODEL must be set.
"""
# ADM check that the DESIMODEL environment variable is set.
if os.environ.get('DESIMODEL') is None:
msg = "DESIMODEL environment variable must be set!!!"
log.critical(msg)
raise ValueError(msg)
# ADM the resolution at which the healpix files are stored.
nside = _get_gaia_nside()
# ADM check that the GAIA_DIR is set and retrieve it.
gaiadir = get_gaia_dir()
hpxdir = os.path.join(gaiadir, 'healpix')
# ADM determine the pixels that touch the tiles.
from desimodel.footprint import tiles2pix
pixnum = tiles2pix(nside, tiles=tiles)
# ADM if neighbors was sent, then retrieve all pixels that touch each
# ADM pixel covered by the provided locations, to prevent edge effects...
if neighbors:
pixnum = add_hp_neighbors(nside, pixnum)
# ADM reformat in the Gaia healpix format used by desitarget.
gaiafiles = [os.path.join(hpxdir, io.hpx_filename(pn)) for pn in pixnum]
return gaiafiles
def find_tycho_files_hp(nside, pixlist, neighbors=True):
"""Find full paths to Tycho healpix files in a set of HEALPixels.
Parameters
----------
nside : :class:`int`
(NESTED) HEALPixel nside.
pixlist : :class:`list` or `int`
A set of HEALPixels at `nside`.
neighbors : :class:`bool`, optional, defaults to ``True``
Also return files corresponding to all neighbors that touch the
pixels in `pixlist` to prevent edge effects (e.g. a Tycho source
is 1 arcsec outside of `pixlist` and so in an adjacent pixel).
Returns
-------
:class:`list`
A list of all Tycho files that need to be read in to account for
objects in the passed list of pixels.
Notes
-----
- The environment variable $TYCHO_DIR must be set.
"""
# ADM the resolution at which the healpix files are stored.
filenside = get_tycho_nside()
# ADM check that the TYCHO_DIR is set and retrieve it.
tychodir = get_tycho_dir()
hpxdir = os.path.join(tychodir, 'healpix')
# ADM work with pixlist as an array.
pixlist = np.atleast_1d(pixlist)
# ADM determine the pixels that touch the passed pixlist.
pixnum = nside2nside(nside, filenside, pixlist)
# ADM if neighbors was sent, then retrieve all pixels that touch each
# ADM pixel covered by the provided locations, to prevent edge effects...
if neighbors:
pixnum = add_hp_neighbors(filenside, pixnum)
# ADM reformat in the healpix format used by desitarget.
tychofiles = [os.path.join(hpxdir, io.hpx_filename(pn)) for pn in pixnum]
return tychofiles
def find_gaia_files_box(gaiabounds, neighbors=True):
"""Find full paths to Gaia healpix files in an RA/Dec box.
Parameters
----------
gaiabounds : :class:`list`
A region of the sky bounded by RA/Dec. Pass as a 4-entry list to
represent an area bounded by [RAmin, RAmax, DECmin, DECmax]
neighbors : :class:`bool`, optional, defaults to ``True``
Also return files corresponding to all neighboring pixels that touch
the files that touch the box in order to prevent edge effects (e.g. if a Gaia
source might be 1 arcsec outside of the box and so in an adjacent pixel)
Returns
-------
:class:`list`
A list of all Gaia files that need to be read in to account for objects
in the passed box.
Notes
-----
- Uses the `healpy` routines that rely on `fact`, so the usual
warnings about returning different pixel sets at different values
of `fact` apply. See:
https://healpy.readthedocs.io/en/latest/generated/healpy.query_polygon.html
- The environment variable $GAIA_DIR must be set.
"""
# ADM the resolution at which the healpix files are stored.
nside = _get_gaia_nside()
# ADM check that the GAIA_DIR is set and retrieve it.
gaiadir = get_gaia_dir()
hpxdir = os.path.join(gaiadir, 'healpix')
# ADM determine the pixels that touch the box.
pixnum = hp_in_box(nside, gaiabounds, inclusive=True, fact=4)
# ADM if neighbors was sent, then retrieve all pixels that touch each
# ADM pixel covered by the provided locations, to prevent edge effects...
if neighbors:
pixnum = add_hp_neighbors(nside, pixnum)
# ADM reformat in the Gaia healpix format used by desitarget.
gaiafiles = [os.path.join(hpxdir, io.hpx_filename(pn)) for pn in pixnum]
return gaiafiles
def find_gaia_files_beyond_gal_b(mingalb, neighbors=True):
"""Find full paths to Gaia healpix files beyond a Galactic b.
Parameters
----------
mingalb : :class:`float`
Closest latitude to Galactic plane to return HEALPixels
(e.g. send 10 to limit to pixels beyond -10o <= b < 10o).
neighbors : :class:`bool`, optional, defaults to ``True``
Also return files corresponding to neighboring pixels that touch
in order to prevent edge effects (e.g. if a Gaia source might be
1 arcsec beyond mingalb and so in an adjacent pixel).
Returns
-------
:class:`list`
All Gaia files that need to be read in to account for objects
further from the Galactic plane than `mingalb`.
Notes
-----
- The environment variable $GAIA_DIR must be set.
- :func:`desitarget.geomask.hp_beyond_gal_b()` is already quite
inclusive, so you may retrieve some extra files along the
`mingalb` boundary.
"""
# ADM the resolution at which the healpix files are stored.
nside = _get_gaia_nside()
# ADM check that the GAIA_DIR is set and retrieve it.
gaiadir = get_gaia_dir()
hpxdir = os.path.join(gaiadir, 'healpix')
# ADM determine the pixels beyond mingalb.
pixnum = hp_beyond_gal_b(nside, mingalb, neighbors=True)
# ADM if neighbors was sent, retrieve all pixels that touch each
# ADM retrieved, to prevent edge effects...
if neighbors:
pixnum = add_hp_neighbors(nside, pixnum)
# ADM reformat in the Gaia healpix format used by desitarget.
gaiafiles = [os.path.join(hpxdir, io.hpx_filename(pn)) for pn in pixnum]
return gaiafiles
def tycho_fits_to_healpix():
"""Convert files in $TYCHO_DIR/fits to files in $TYCHO_DIR/healpix.
Returns
-------
Nothing
But the archived Tycho FITS files in $TYCHO_DIR/fits are
rearranged by HEALPixel in the directory $TYCHO_DIR/healpix.
The HEALPixel sense is nested with nside=get_tycho_nside(), and
each file in $TYCHO_DIR/healpix is called healpix-xxxxx.fits,
where xxxxx corresponds to the HEALPixel number.
Notes
-----
- The environment variable $TYCHO_DIR must be set.
"""
# ADM the resolution at which the Tycho HEALPix files are stored.
nside = get_tycho_nside()
npix = hp.nside2npix(nside)
# ADM check that the TYCHO_DIR is set.
tychodir = get_tycho_dir()
# ADM construct the directories for reading/writing files.
fitsdir = os.path.join(tychodir, "fits")
tychofn = os.path.join(fitsdir, "tycho2.kd.fits")
hpxdir = os.path.join(tychodir, "healpix")
# ADM make sure the output directory is empty.
if os.path.exists(hpxdir):
if len(os.listdir(hpxdir)) > 0:
msg = "{} must be empty to make Tycho HEALPix files!".format(hpxdir)
log.critical(msg)
raise ValueError(msg)
# ADM make the output directory, if needed.
else:
log.info("Making Tycho directory for storing HEALPix files")
os.makedirs(hpxdir)
# ADM read in the Tycho file and assing Tycho objects to HEALPixels.
objs, allhdr = fitsio.read(tychofn, header=True, upper=True)
pix = radec2pix(nside, objs["RA"], objs["DEC"])
# ADM loop through the pixels and write out the files.
for pixnum in range(npix):
# ADM construct the name of the output file.
outfilename = io.hpx_filename(pixnum)
outfile = os.path.join(hpxdir, outfilename)
# ADM update the header with new information.
hdr = dict(allhdr).copy()
hdr["HPXNSIDE"] = nside
hdr["HPXNEST"] = True
hdr["HPXDATE"] = datetime.utcnow().isoformat(timespec='seconds')
# ADM determine which objects are in this pixel and write out.
done = objs[pix == pixnum]
fitsio.write(outfile, done, extname="TYCHOHPX", header=hdr)
log.info('Wrote Tycho HEALPix files...t={:.1f}s'.format(time()-start))
return
