Other functions

dist2holes(m[, maxdist, hole_min_size, ...])	Computes the distance (in radians) from pixel center to center of closest invalid pixel up to a maximal distance.
hotspots(m)	Find extrema in the 2-D field on the sphere.
ringinfo(nside, ring)	Get information for rings
pix2ring(nside, pix[, nest])	Convert pixel identifier to ring number