diff options
Diffstat (limited to 'fg21sim')
| -rw-r--r-- | fg21sim/utils/healpix.py | 55 |
1 files changed, 20 insertions, 35 deletions
diff --git a/fg21sim/utils/healpix.py b/fg21sim/utils/healpix.py index ea3c45b..f672c78 100644 --- a/fg21sim/utils/healpix.py +++ b/fg21sim/utils/healpix.py @@ -38,17 +38,17 @@ from . import read_fits_healpix logger = logging.getLogger(__name__) -def healpix2hpx(data, header=None, append_history=None, append_comment=None): +def healpix2hpx(data, append_history=None, append_comment=None): """Reorganize the HEALPix data (1D array as FITS table) into 2D FITS image in HPX coordinate system. Parameters ---------- - data : str, `~astropy.io.fits.BinTableHDU`, or 1D `~numpy.ndarray` - The input HEALPix map to be converted to the HPX image. - (1) filename of the HEALPix file; - (2) BinTableHDU containing the HEALPix data and header - (3) 1D array containing the HEALPix data + data : str or `~astropy.io.fits.BinTableHDU` + The input HEALPix map to be converted to the HPX image, + which can be either the filename of the HEALPix FITS file, + or be a `~astropy.io.fits.BinTableHDU` instance containing + the HEALPix data as well as its header. header : `~astropy.io.fits.Header`, optional Header of the HEALPix FITS file append_history : list[str] @@ -63,25 +63,15 @@ def healpix2hpx(data, header=None, append_history=None, append_comment=None): hpx_header : `~astropy.io.fits.Header` FITS header for the HPX image """ - if isinstance(data, str) or isinstance(data, fits.BinTableHDU): - hp_data, hp_header = read_fits_healpix(data) - logger.info("Read HEALPix data from file or HDU") - else: - hp_data, hp_header = np.asarray(data), fits.header.Header(header) - logger.info("Read HEALPix data from array and header") + hp_data, hp_header = read_fits_healpix(data) dtype = hp_data.dtype - logger.info("HEALPix dtype: {0}".format(dtype)) - logger.info("HEALPix index ordering: %s" % hp_header["ORDERING"]) - if hp_header["ORDERING"] != "RING": - raise ValueError("only 'RING' ordering currently supported") npix = len(hp_data) nside = hp.npix2nside(npix) - logger.info("HEALPix data: Npix=%d, Nside=%d" % (npix, nside)) - if nside != hp_header["NSIDE"]: - raise ValueError("HEALPix data Nside does not match the header") + logger.info("Loaded HEALPix data: dtype={0}, Npixel={1}, Nside={2}".format( + dtype, npix, nside)) hp_data = np.append(hp_data, np.nan).astype(dtype) hpx_idx = _calc_hpx_indices(nside) - # fix indices of "-1" to set empty pixels with above appended "nan" + # Fix indices of "-1" to set empty pixels with above appended NaN hpx_idx[hpx_idx == -1] = len(hp_data) - 1 hpx_data = hp_data[hpx_idx] hpx_header = _make_hpx_header(hp_header, @@ -90,19 +80,17 @@ def healpix2hpx(data, header=None, append_history=None, append_comment=None): return (hpx_data.astype(hp_data.dtype), hpx_header) -def hpx2healpix(data, header=None, append_history=None, append_comment=None): +def hpx2healpix(data, append_history=None, append_comment=None): """Revert the reorganization and turn the 2D image in HPX format back into HEALPix data as 1D array. Parameters ---------- - data : str, `~astropy.io.fits.PrimaryHDU`, or 2D `~numpy.ndarray` - The input HPX image to be converted to the HEALPix data. - (1) filename of the HPX file; - (2) PrimaryHDU containing the HPX image and header - (3) 2D array containing the HPX image - header : `~astropy.io.fits.Header`, optional - Header of the HPX FITS image + data : str or `~astropy.io.fits.PrimaryHDU` + The input HPX image to be converted to the HEALPix data, + which can be either the filename of the HPX FITS image, + or be a `~astropy.io.fits.PrimaryHDU` instance containing + the HPX image as well as its header. append_history : list[str] Append the provided history to the output FITS header append_comment : list[str] @@ -118,20 +106,17 @@ def hpx2healpix(data, header=None, append_history=None, append_comment=None): if isinstance(data, str): hpx_hdu = fits.open(data)[0] hpx_data, hpx_header = hpx_hdu.data, hpx_hdu.header - logger.info("Read HPX image from file") - elif isinstance(data, fits.PrimaryHDU): - hpx_data, hpx_header = data.data, data.header - logger.info("Read HPX image from HDU") + logger.info("Read HPX image from FITS file: %s" % data) else: - hpx_data, hpx_header = np.asarray(data), fits.header.Header(header) - logger.info("Read HPX image from array and header") + hpx_data, hpx_header = data.data, data.header + logger.info("Read HPX image from PrimaryHDU") logger.info("HPX image dtype: {0}".format(hpx_data.dtype)) logger.info("HPX coordinate system: ({0}, {1})".format( hpx_header["CTYPE1"], hpx_header["CTYPE2"])) if ((hpx_header["CTYPE1"], hpx_header["CTYPE2"]) != ("GLON-HPX", "GLAT-HPX")): raise ValueError("only Galactic 'HPX' projection currently supported") - # calculate Nside + # Calculate Nside nside = round(hpx_header["NAXIS1"] / 5) nside2 = round(90 / np.sqrt(2) / hpx_header["CDELT2"]) if nside != nside2: |