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/*! \libinternal
 * \file
 * \brief
 * Declares routine for computing a cross correlation between two data sets
 *
 * \author David van der Spoel <david.vanderspoel@icm.uu.se>
 * \inlibraryapi
 * \ingroup module_correlationfunctions
 */
#ifndef GMX_CROSSCORR_H
#define GMX_CROSSCORR_H

#include "gromacs/utility/real.h"

/*! \brief
 * fft cross correlation algorithm.
 * Computes corr = f (.) g
 *
 * \param[in] n number of data point
 * \param[in] f First function
 * \param[in] g Second function
 * \param[out] corr The cross correlation
 */
void cross_corr(int n, real f[], real g[], real corr[]);

/*! \brief
 * fft cross correlation algorithm.
 *
 * Computes corr[n] = f[n][i] (.) g[n][i], that is for nFunc
 * pairs of arrays n the cross correlation is computed in parallel
 * using OpenMP.
 *
 * \param[in] nFunc nuber of function to crosscorrelate
 * \param[in] nData number of data point in eatch function
 * \param[in] f 2D array of first function to crosscorrelate
 * \param[in] g 2D array of second function to crosscorrelate
 * \param[out] corr 2D array of the cross correlations
 */
void many_cross_corr(int nFunc, int* nData, real** f, real** g, real** corr);

#endif
