needlets.filtermap_fromalm

filtermap_fromalm(alm, bl, nside, returnalm=False)[source]

Filter the map (given by its alm) with an input needlet.

Parameters

  • alm (np.ndarray) – The alm of a Healpy map of the sky, as given by hp.map2alm()

  • bl (np.ndarray) – A numpy array containing the values of a needlet filter b(l), starting with l=0.

  • nside (int) – The nside of the input map. The output map will also have this nside.

  • returnalm (bool, optional) – If True, the function will also return the alm for the filtered map.

Returns

If returnalm=False, filtered map in the Healpix format. If returnalm=True, a list with the filtered map and its corresponding alm.

Return type

np.ndarray or [np.ndarray,np.ndarray]