alm_powspec_tools.h

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/*
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/*
 *  Healpix_cxx is being developed at the Max-Planck-Institut fuer Astrophysik
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/*! \file alm_powspec_tools.h
 *  Copyright (C) 2003-2014 Max-Planck-Society
 *  \author Martin Reinecke
 */

#ifndef PLANCK_ALM_POWSPEC_TOOLS_H
#define PLANCK_ALM_POWSPEC_TOOLS_H

#include "xcomplex.h"

template<typename T> class Alm;
class PowSpec;
class planck_rng;
class rotmatrix;

/*! \defgroup alm_ps_group Conversions between a_lm and power spectra */
/*! \{ */

/*! Creates a Gaussian realisation of the input power spectrum \a powspec,
    using the random number generator \a rng, and returns the result
    in \a alm. */
template<typename T> void create_alm (const PowSpec &powspec,
  Alm<xcomplex<T> > &alm, planck_rng &rng);

/*! Creates a Gaussian realisation of the polarised input power spectrum
    \a powspec, using the random number generator \a rng, and returns the
    result in \a almT, \a almG and \a almC. */
template<typename T> void create_alm_pol
  (const PowSpec &powspec,
   Alm<xcomplex<T> > &almT,
   Alm<xcomplex<T> > &almG,
   Alm<xcomplex<T> > &almC,
   planck_rng &rng);

/*! Returns the unpolarised power spectrum of \a alm in \a powspec. */
template<typename T> void extract_powspec
  (const Alm<xcomplex<T> > &alm, PowSpec &powspec);
/*! Returns the cross power spectrum of \a alm1 and \a alm2 in \a powspec. */
template<typename T> void extract_crosspowspec
  (const Alm<xcomplex<T> > &alm1,
   const Alm<xcomplex<T> > &alm2, PowSpec &powspec);
/*! Returns the polarised power spectrum of \a almT, \a almG and \a almC
    in \a powspec. */
template<typename T> void extract_powspec
  (const Alm<xcomplex<T> > &almT,
   const Alm<xcomplex<T> > &almG,
   const Alm<xcomplex<T> > &almC,
   PowSpec &powspec);

/*! \} */

/*! Applies a convolution with a Gaussian beam with an FWHM of
    \a fwhm (in radian) to \a alm.
    \note If \a fwhm<0, a deconvolution with \a -fwhm is performed.
    \relates Alm */
template<typename T> void smoothWithGauss
  (Alm<xcomplex<T> > &alm, double fwhm);
/*! Applies a convolution with a Gaussian beam with an FWHM of
    \a fwhm (in radian) to \a almT, \a almG and \a almC.
    \note If \a fwhm<0, a deconvolution with \a -fwhm is performed.
    \relates Alm */
template<typename T> void smoothWithGauss
  (Alm<xcomplex<T> > &almT,
   Alm<xcomplex<T> > &almG,
   Alm<xcomplex<T> > &almC,
   double fwhm);

/*! Applies a function to \a alm that is 1 for all \c l<=lmin, 0 for all
    \c l>=lmax, and \c 0.5*(1+cos((l-lmin)/(lmax-lmin)*pi)) in between.
    \relates Alm  */
template<typename T> void applyCosineWindow
  (Alm<xcomplex<T> > &alm, int lmin, int lmax);

template<typename T> inline void applyCosineWindow
  (Alm<xcomplex<T> > &almT, Alm<xcomplex<T> > &almG, Alm<xcomplex<T> > &almC,
  int lmin, int lmax)
  {
  applyCosineWindow(almT,lmin,lmax);
  applyCosineWindow(almG,lmin,lmax);
  applyCosineWindow(almC,lmin,lmax);
  }

/*! Rotates \a alm through the Euler angles \a psi, \a theta and \a phi.
    The Euler angle convention  is right handed, rotations are active.
    - \a psi is the first rotation about the z-axis (vertical)
    - then \a theta about the ORIGINAL (unrotated) y-axis
    - then \a phi  about the ORIGINAL (unrotated) z-axis (vertical)
    \relates Alm */
template<typename T> void rotate_alm (Alm<xcomplex<T> > &alm,
  double psi, double theta, double phi);

/*! Rotates \a almT, \a almG and \a almC through the Euler angles
    \a psi, \a theta and \a phi.
    The Euler angle convention  is right handed, rotations are active.
    - \a psi is the first rotation about the z-axis (vertical)
    - then \a theta about the ORIGINAL (unrotated) y-axis
    - then \a phi  about the ORIGINAL (unrotated) z-axis (vertical)
    \relates Alm */
template<typename T> void rotate_alm (Alm<xcomplex<T> > &almT,
  Alm<xcomplex<T> > &almG, Alm<xcomplex<T> > &almC,
  double psi, double theta, double phi);

/*! Rotates \a alm through the rotation matrix \a mat.
    \relates Alm */
template<typename T> void rotate_alm (Alm<xcomplex<T> > &alm,
  const rotmatrix &mat);

/*! Rotates \a almT, \a almG and \a almC through the rotation matrix \a mat.
    \relates Alm */
template<typename T> void rotate_alm (Alm<xcomplex<T> > &almT,
  Alm<xcomplex<T> > &almG, Alm<xcomplex<T> > &almC,
  const rotmatrix &mat);

#endif