Thread: Moving Average (from and into an array)

If your window size is 5, and you want non-overlapping windows, then try a test with an array that looks like this
1,1,1,1,1,2,2,2,2,2,3,3,3,3,3,4,4,4,4,4,5,5,5,5,5

The answer should be obvious. If your code produces that answer, you might be onto something.
If it doesn't, it's broke.

Post a small complete example we can just copy, paste, compile and run.

Code:

#include <stdio.h>
#include <stdlib.h>
#include <math.h>
#include <string.h>


int main(void)
{
	FILE*		input;
	const char	input_fn[]="proj3input.dat";
	char 		        buf[1025];
	char 		        *tokptr, *strptr = buf;
	int			col=0, line_num=0, win_min, win_max, win_size, i=0, j=0, x=0, record=0, curr_col, initial, tmp2, p, q;
	double		*tdata, *ydata, *tmean, *ymean, tmp, tsum, ysum;
	
	input=fopen("proj3input.dat","r");
	
	/*Verify file*/
	if (input==(FILE*) NULL)
        {
	    printf("Cannot open required file!\n");
            printf("Please ensure your data file\n");
	    printf("is in the correct directory\n");
	    exit(EXIT_FAILURE);
	}
	else
	
	/*Count number of lines*/
	{
		while((fgets(buf, 1024, input) != NULL))
		{
			line_num++;
		}
		printf("Number of lines is %d \n", line_num);
	}
	
	rewind(input);
	
	fgets(buf, 1024, input);
       while((tokptr=(char*)strtok(strptr, " \t")) != NULL)
       {
               strptr = NULL;
               col++;
       }
	
	printf("Number of columns is %d \n", col);
	
	rewind(input);
	
	/* Find minimum and maximum sizes of window */

        win_min = 10;
        win_max = line_num;
	
	/* Read user input for window size */

	printf("Please enter your desired window size.\n");
	printf("This should be between %d and %d.\n", win_min, win_max);
        scanf("%s", buf);
        win_size = atoi(buf);
	
	printf("Your window size will be %d\n", win_size);
	
	/* Allocate memory space */
	
	tdata = (double*) malloc((line_num)*sizeof(double));
        ydata = (double*) malloc((line_num)*sizeof(double));
	tmean = (double*) malloc((win_size)*sizeof(double));
	ymean = (double*) malloc((win_size)*sizeof(double));
        printf("Allocated memory for %d records\n",line_num);
	
	rewind(input);
	
	while(fscanf(input, "%lf", &tmp) == 1)
	{
		curr_col = (record % col) + 1;
		if(curr_col==1)
	        {
			tdata[i] = tmp;
		}
		else
		{
			ydata[i] = tmp;
			i++;
		}
		record++;
	}
	fclose(input);
	for(x=9990; x<10000; x++)
	{
		printf("(%lf %lf)\n", tdata[x], ydata[x]);
	}
	i=0;
	for(p=0; p<(win_size/line_num); p++)
	{
		for(i=win_size*p; i<((win_size*p)+win_size); i++)
		{
			tsum=0;
			ysum=0;
			tsum = tsum + tdata[i];
			ysum = ysum + ydata[i];
                        tmean[q] = tsum/win_size;
		        ymean[q] = ysum/win_size;
		}

	}
	printf("Tmean is %lf, Ymean is %lf\n", tmean[0], ymean[0]);
}

data file in 2 columns named proj3input.dat

Thanks