_FIR1D(3F)							    _FIR1D(3F)

NAME    [Toc]    [Back]

     SFIR1D, DFIR1D, CFIR1D, ZFIR1D - 1D Convolution in	the time domain.

FORTRAN	SPECIFICATION
     subroutine	SFIR1D(	in_put,	incinp,	i0_inp,	n_inp,
			firfil,	incfir,	i0_fir,	n_fir,
			output,	incout,	i0_out,	n_out,
			alpha, beta )
     integer		incinp,	i0_inp,	n_inp,
			incfir,	i0_fir,	n_fir
			incout,	i0_out,	n_out
     real		in_put(*), firfil(*), output(*), alpha,	beta

     subroutine	DFIR1D(	in_put,	incinp,	i0_inp,	n_inp,
			firfil,	incfir,	i0_fir,	n_fir,
			output,	incout,	i0_out,	n_out,
			alpha, beta )
     integer		incinp,	i0_inp,	n_inp,
			incfir,	i0_fir,	n_fir
			incout,	i0_out,	n_out
     double precision	in_put(*), firfil(*), output(*), alpha,	beta

     subroutine	CFIR1D(	in_put,	incinp,	i0_inp,	n_inp,
			firfil,	incfir,	i0_fir,	n_fir,
			output,	incout,	i0_out,	n_out,
			alpha, beta )
     integer		incinp,	i0_inp,	n_inp,
			incfir,	i0_fir,	n_fir
			incout,	i0_out,	n_out
     complex		in_put(*), firfil(*), output(*), alpha,	beta

     subroutine	ZFIR1D(	in_put,	incinp,	i0_inp,	n_inp,
			firfil,	incfir,	i0_fir,	n_fir,
			output,	incout,	i0_out,	n_out,
			alpha, beta )
     integer		incinp,	i0_inp,	n_inp,
			incfir,	i0_fir,	n_fir
			incout,	i0_out,	n_out
     double complex	in_put(*), firfil(*), output(*), alpha,	beta

C SPECIFICATION    [Toc]    [Back]

     #include <conv.h>

     void sfir1d(    float *f, int incf, int if0, int nf,
		     float *g, int incg, int ig0, int ng,
		     float *h, int inch, int ih0, int nh,
		     float alpha, float	beta)

     void dfir1d(    double *f,	int incf, int if0, int nf,
		     double *g,	int incg, int ig0, int ng,
		     double *h,	int inch, int ih0, int nh,



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_FIR1D(3F)							    _FIR1D(3F)



		     double alpha, double beta)

     void cfir1d(    complex *f, int incf, int if0, int	nf,
		     complex *g, int incg, int ig0, int	ng,
		     complex *h, int inch, int ih0, int	nh,
		     complex *alpha, complex *beta)

     void zfir1d(    zomplex *f, int incf, int if0, int	nf,
		     zomplex *g, int incg, int ig0, int	ng,
		     zomplex *h, int inch, int ih0, int	nh,
		     zomplex *alpha, zomplex *beta)

DESCRIPTION    [Toc]    [Back]

     SFIR1D and	DFIR1D compute a 1D convolution	in the time domain :

	    O(j) = Sum[	I(i) * F(j-i) ]

USAGE    [Toc]    [Back]

     These modules compute the result of the convolution in the	"output" range
     padding with zeroes when needed. In theory, an input sequence of "n_inp"
     samples starting at time "i0_inp",	filtered by a sequence of "n_fir"
     samples starting at time "i0_fir",	will result in a new signal of (n_inp
     + n_fir - 1) non zero samples starting at time (i0_inp + i0_fir). We just
     compute here the values that fall in that range and zero the rest.	 This
     may be interesting, for example when filtering a sequence of N samples,
     with a symmetric filter of	2m+1 samples. If one wants only	to compute the
     central N resulting samples, the following	call can be used:
	 call _fir1d( f, 0, 1, N,  g, -m, 1, 2*m+1,  h,	0, 1, N)

PARAMETERS    [Toc]    [Back]

     in_put  Pointer to	FIRST sample of	sequence "in_put"


     incinp  Increment between two successive values of	"in_put"


     i0_inp  Index of the first	element	of "in_put"


     n_inp   Number of samples of "in_put"


     firfil  Pointer to	FIRST sample of	sequence "firfil"







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_FIR1D(3F)							    _FIR1D(3F)



     incfir  Increment between two successive values of	"firfil"


     i0_fir  Index of the first	element	of "firfil"


     i0_fir  Number of samples of "firfil"


     output  Pointer to	FIRST sample of	sequence "output"


     incout  Increment between two successive values of	"output"


     i0_out  Index of the first	element	of "output"


     n_out   Number of samples of "output"


     alpha   Scaling factor for	the convolution


     beta    Scaling factor for	the Output on Entry


IMPORTANT NOTE:
	   The array pointers must all point to	the first element of the
	   array "i0_inp", "i0_fir" and	"i0_out". If "in_put" for example
	   is defined as
		dimension in_put(-25:45)
	   Then	"dfir1d" must be called	with the following parameters
		call dfir1d( in_put(-25),1,-25,45, ... )

AUTHORS    [Toc]    [Back]

	  Jean-Pierre Panziera,	1/12/93.


									PPPPaaaaggggeeee 3333