corr.c File Reference

#include "tools.h"
#include <stdlib.h>
#include <stdio.h>

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Functions
void	corr (int N, float x[N], float y[N], int M, float R[M])
	corr.c - sample cross correlation of two length-N signals More...
int	main (int argc, char **argv)

Function Documentation

corr()

void corr	(	int	N,
		float	x[N],
		float	y[N],
		int	M,
		float	R[M]
	)

corr.c - sample cross correlation of two length-N signals

computes (R[k]), (k = 0, 1,\dotsc, M) (x,y) are (N)-dimensional (R) is ((M+1))-dimensional

Definition at line 5 of file corr.c.

{
       int k, n;
 
       for (k=0; k<M; k++)
              for (R[k]=0, n=0; n<N-k; n++)
                     R[k] += x[n+k] * y[n] / N;
}

References x.

Referenced by main().

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main()

int main	(	int	argc,
		char **	argv
	)

Definition at line 19 of file corr.c.

                                {
        int n = atoi(argv[1]);
        int k = 5;
        //int k = atoi(argv[3]);
        float (*in)[n] = (float (*)[n])malloc(sizeof(float)*(1+n));
        float (*in2)[n] = (float (*)[n])malloc(sizeof(float)*(1+n));
        float (*out)[k] = (float (*)[n])malloc(sizeof(float)*(k));
        init_args(argc, argv);
        init_data_float(*in,n);
        init_data_float(*in2,n);
 
        if (argc>20) k=10;
        struct timeval s,e;
        gettimeofday(&s,NULL);
        corr(n,*in,*in2,k,*out);
        gettimeofday(&e,NULL);
        double diff = (double)(e.tv_sec-s.tv_sec)*1000.0 +
                (double)(e.tv_usec-s.tv_usec)/1000.0;
        printf("%0.6f\n", diff);
        return 0;
}

References corr(), init_args(), init_data_float(), malloc(), out, and printf().

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