cosmotool/external/sharp/libsharp/sharp_ylmgen_c.h
2012-11-10 09:01:12 -05:00

100 lines
3 KiB
C

/*
* This file is part of libsharp.
*
* libsharp is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* libsharp is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with libsharp; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
/*
* libsharp is being developed at the Max-Planck-Institut fuer Astrophysik
* and financially supported by the Deutsches Zentrum fuer Luft- und Raumfahrt
* (DLR).
*/
/*! \file sharp_ylmgen_c.h
* Code for efficient calculation of Y_lm(phi=0,theta)
*
* Copyright (C) 2005-2012 Max-Planck-Society
* \author Martin Reinecke
*/
#ifndef SHARP_YLMGEN_C_H
#define SHARP_YLMGEN_C_H
#ifdef __cplusplus
extern "C" {
#endif
enum { sharp_minscale=0, sharp_limscale=1, sharp_maxscale=1 };
static const double sharp_fbig=0x1p+800,sharp_fsmall=0x1p-800;
static const double sharp_ftol=0x1p-60;
static const double sharp_fbighalf=0x1p+400;
typedef struct { double f[2]; } sharp_ylmgen_dbl2;
typedef struct { double f[3]; } sharp_ylmgen_dbl3;
typedef struct
{
/* for public use; immutable during lifetime */
int lmax, mmax, s;
double *cf;
/* for public use; will typically change after call to Ylmgen_prepare() */
int m;
/* used if s==0 */
double *mfac;
sharp_ylmgen_dbl2 *rf;
/* used if s!=0 */
int sinPow, cosPow, preMinus_p, preMinus_m;
double *prefac;
int *fscale;
sharp_ylmgen_dbl3 *fx;
/* internal usage only */
/* used if s==0 */
double *root, *iroot;
/* used if s!=0 */
double *flm1, *flm2, *inv;
int mlo, mhi;
} sharp_Ylmgen_C;
/*! Creates a generator which will calculate helper data for Y_lm calculation
up to \a l=l_max and \a m=m_max. */
void sharp_Ylmgen_init (sharp_Ylmgen_C *gen, int l_max, int m_max, int spin);
/*! Deallocates a generator previously initialised by Ylmgen_init(). */
void sharp_Ylmgen_destroy (sharp_Ylmgen_C *gen);
/*! Prepares the object for the calculation at \a m. */
void sharp_Ylmgen_prepare (sharp_Ylmgen_C *gen, int m);
/*! Returns a pointer to an array with \a lmax+1 entries containing
normalisation factors that must be applied to Y_lm values computed for
\a spin. The array must be deallocated (using free()) by the user. */
double *sharp_Ylmgen_get_norm (int lmax, int spin);
/*! Returns a pointer to an array with \a lmax+1 entries containing
normalisation factors that must be applied to Y_lm values computed for
first derivatives. The array must be deallocated (using free()) by the
user. */
double *sharp_Ylmgen_get_d1norm (int lmax);
#ifdef __cplusplus
}
#endif
#endif