reproject.reproject_from_healpix(input_data, output_projection, shape_out=None, hdu_in=None, order='bilinear', nested=False, field=0)[source]

Reproject data from a HEALPIX projection to a standard projection.


This function uses healpy, which is licensed under the GPLv2, so any package using this funtions has to (for now) abide with the GPLv2 rather than the BSD license.


input_data : str or TableHDU or BinTableHDU or tuple

The input data to reproject. This can be:

output_projection : WCS or Header

The output projection, which can be either a WCS or a Header instance.

shape_out : tuple, optional

If output_projection is a WCS instance, the shape of the output data should be specified separately.

hdu_in : int or str, optional

If input_data is a FITS file, specifies the HDU to use.

order : int or str, optional

The order of the interpolation (if mode is set to 'interpolation'). This can be either one of the following strings:

  • ‘nearest-neighbor’
  • ‘bilinear’

or an integer. A value of 0 indicates nearest neighbor interpolation.

nested : bool, optional

The order of the healpix_data, either nested (True) or ring (False)

field : int, optional

The column to read from the HEALPIX FITS file. If the fits file is a partial-sky file, field=0 corresponds to the first column after the pixel index column.


array_new : ndarray

The reprojected array

footprint : ndarray

Footprint of the input array in the output array. Values of 0 indicate no coverage or valid values in the input image, while values of 1 indicate valid values.