boundaries_lonlat

astropy_healpix.boundaries_lonlat(healpix_index, step, nside, order='ring')

Return the longitude and latitude of the edges of HEALPix pixels

This returns the longitude and latitude of points along the edge of each HEALPIX pixel. The number of points returned for each pixel is 4 * step, so setting step to 1 returns just the corners.

Parameters:

healpix_indexndarray

1-D array of HEALPix pixels

stepint

The number of steps to take along each edge.

nsideint

Number of pixels along the side of each of the 12 top-level HEALPix tiles

order{ ‘nested’ | ‘ring’ }

Order of HEALPix pixels

Returns:

lon, latQuantity

The longitude and latitude, as 2-D arrays where the first dimension is the same as the healpix_index input, and the second dimension has size 4 * step.