# sphtfunc – Spherical harmonic transforms¶

## From map to spherical harmonics¶

 anafast(map1[, map2, nspec, lmax, mmax, …]) Computes the power spectrum of a Healpix map, or the cross-spectrum between two maps if map2 is given. map2alm(maps[, lmax, mmax, iter, pol, …]) Computes the alm of a Healpix map. map2alm_spin Computes the spinned alm of a 2 Healpix maps.

## From spherical harmonics to map¶

 synfast(cls, nside[, lmax, mmax, alm, pol, …]) Create a map(s) from cl(s). alm2map(alms, nside[, lmax, mmax, pixwin, …]) Computes a Healpix map given the alm. alm2map_der1(alm, nside[, lmax, mmax]) Computes a Healpix map and its first derivatives given the alm. alm2map_spin Computes maps from a set of 2 spinned alm

## Spherical harmonic transform tools¶

 smoothing(map_in[, fwhm, sigma, …]) Smooth a map with a Gaussian symmetric beam. smoothalm(alms[, fwhm, sigma, beam_window, …]) Smooth alm with a Gaussian symmetric beam function. alm2cl(alms1[, alms2, lmax, mmax, lmax_out, …]) Computes (cross-)spectra from alm(s). synalm(cls[, lmax, mmax, new, verbose]) Generate a set of alm given cl. almxfl(alm, fl[, mmax, inplace]) Multiply alm by a function of l. pixwin(nside[, pol, lmax]) Return the pixel window function for the given nside. Alm() This class provides some static methods for alm index computation.

## Other tools¶

 gauss_beam(fwhm[, lmax, pol]) Gaussian beam window function beam2bl(beam, theta, lmax) Computes a transfer (or window) function b(l) in spherical harmonic space from its circular beam profile b(theta) in real space. bl2beam(bl, theta) Computes a circular beam profile b(theta) in real space from its transfer (or window) function b(l) in spherical harmonic space.