fftlib.h

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/* © 1998 JRM Technologies, Inc.*/
/***********************************************************
Copyright JRM Enterprises, Inc. 1998
All rights reserved.

This code is the intellectual property of JRM Enteprises, Inc.
developed for the Institute for Defense Analysis (IDA).

JRM Enterprises, Inc. grants the Insitute for Defense Analysis
the right to use and distribute this code as necessary for
Government purposes.

No third party may use or distribute this code without
prior written consent of JRM Enterprises, Inc. or Institute
for Defense Analysis.
************************************************************/

#ifndef _JRMLIBRARY_FFTLIB_H_
#define _JRMLIBRARY_FFTLIB_H_

#include "JRMlibrary.h"
#include "JRMlibraryDLLstub.h"

#ifdef __cplusplus
extern "C"
{
#endif


#define     c_re(c)     ((c).re)
#define     c_im(c)     ((c).im)

    /*
    * C_add_mul adds product of c1 and c2 to c.
    */
#define  c_add_mul(c, c1, c2) { COMPLEX C1, C2; C1 = (c1); C2 = (c2);              c_re (c) += C1.re * C2.re - C1.im * C2.im; c_im (c) += C1.re * C2.im + C1.im * C2.re; }

    /*
    * C_conj substitutes c by its complex conjugate.
    */
#define c_conj(c)    { c_im (c) = -c_im (c); }

    /*
    * C_realdiv divides complex c by real.
    */
#define  c_realdiv(c, real)   { c_re (c) /= (real); c_im (c) /= (real); }

    JRMLIBRARY_API extern COMPLEX *W_factors;
    JRMLIBRARY_API extern unsigned Nfactors;


    JRMLIBRARY_API COMPLEX Convert2COMPLEX(jrmComplex x);
    JRMLIBRARY_API jrmComplex Convert2complex(COMPLEX x);
    JRMLIBRARY_API COMPLEX AddCOMPLEX(COMPLEX a, COMPLEX b);
    JRMLIBRARY_API int AddCOMPLEXArrays(COMPLEX *a, COMPLEX *b, COMPLEX *out, unsigned int nelements);

    /*
    -------------------------------------------------------------------------
    1D FFT
    -------------------------------------------------------------------------
    */


    JRMLIBRARY_API long W_init (unsigned n);
    JRMLIBRARY_API void Fourier (COMPLEX *in, unsigned n, COMPLEX *out);
    JRMLIBRARY_API extern long fft (COMPLEX *in, unsigned n, COMPLEX *out);
    JRMLIBRARY_API extern long fftp (COMPLEX *in, unsigned n, COMPLEX *out);
    JRMLIBRARY_API extern long rft (COMPLEX *in, unsigned n, COMPLEX *out);
    JRMLIBRARY_API extern long rftp (COMPLEX *in, unsigned n, COMPLEX *out);
    JRMLIBRARY_API extern long prime_factor(long n);
    //JRMLIBRARY_API extern long *all_factors(long n, long *count);
    JRMLIBRARY_API extern long next_best(long n, long lpfa);
    JRMLIBRARY_API short dft(COMPLEX *array, long npts, COMPLEX *work, long dir);

    // NOTE : frequency and width inputs to the routines below must be in [#cycles per time interval between array elements],  = [#cycles/sec]*[delta-t = sec/interval]
    JRMLIBRARY_API int LowPassFilter(COMPLEX *in, unsigned int nin, COMPLEX *out, double kneefreq, double attenuation);
    JRMLIBRARY_API int BandPassFilter(COMPLEX *in, unsigned int nin, COMPLEX *out, double centerfreq, double passwidth, double attenuation);
    JRMLIBRARY_API int LocalOscillator(COMPLEX *out, unsigned int nout, double freq, double amplitude);


    /*
    -------------------------------------------------------------------------
    2D FFT
    -------------------------------------------------------------------------
    */

    JRMLIBRARY_API extern long fft2d(COMPLEX *array, long ncols, long nrows, long dirflag, char printflag);
    JRMLIBRARY_API extern long xfmrows(COMPLEX *array, long ncols, long nrows, long dirflag);
    JRMLIBRARY_API extern long xfmcols(COMPLEX *array, long ncols, long nrows, long dirflag);


#ifdef __cplusplus
}
#endif

#endif // _JRMLIBRARY_FFTLIB_H_