@_hidden<EOL><INDENT>def add_column_healpix(self, name="<STR_LIT>", longitude="<STR_LIT>", latitude="<STR_LIT>", degrees=True, healpix_order=<NUM_LIT:12>, nest=True):<DEDENT>
import healpy as hp<EOL>if degrees:<EOL><INDENT>scale = "<STR_LIT>"<EOL><DEDENT>else:<EOL><INDENT>scale = "<STR_LIT>"<EOL><DEDENT>phi = self.evaluate("<STR_LIT>" % (longitude, scale))<EOL>theta = self.evaluate("<STR_LIT>" % (latitude, scale))<EOL>hp_index = hp.ang2pix(hp.order2nside(healpix_order), theta, phi, nest=nest)<EOL>self.add_column("<STR_LIT>", hp_index)<EOL>
Add a healpix (in memory) column based on a longitude and latitude

        :param name: Name of column
        :param longitude: longitude expression
        :param latitude: latitude expression  (astronomical convenction latitude=90 is north pole)
        :param degrees: If lon/lat are in degrees (default) or radians.
        :param healpix_order: healpix order, >= 0
        :param nest: Nested healpix (default) or ring.