Need help for program that uses threshold and blanks!

[BiomedOne]

Hey everyone,

I have an assignment for my biomedical engineering programming class that requires me to calculate the instantaneous heart rate of a given input text file. The professor suggested we use "Threshold and Blanking". My program currently finds the first period's instantaneous heart rate, but how do I make it continue throughout the whole data set?

Any Help is appreciated!

[BiomedOne]

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

FILE *fp;
char fn[100];


int main(int argc, char *argv[]) {

    //declare variables
    int i,j,n;
    float t[10000],b[10000];
    float t1;
    float t2;
    float threshold;
    float blank;
    float tim[20];

    threshold = 120.0;
    blank = 60;

    if(argc!=2) {
        printf("you didn't include the filename silly\n");
    }

    else {
        strcpy(fn,argv[1]);  //put filename on command line
        fp = fopen(fn,"r");    
        if(fp==NULL) {
            printf("error opening file\n");
        }
        else {
            //insert functionality here
            //first find out how many points
            i = 0;
            j = 0;
            while(fscanf(fp,"%g %g",&t[i],&b[i])!=EOF) {
                i++;
            }
            n = i;
            fclose(fp);
    
            i = 0;
            j = 0;
            while(b[i]<threshold) {
                i++;
            }
            tim[j] = t[i];

            printf("t%d = %f\n",j+1,tim[j]);
            //how do i skip over 60 points?
            i = i + blank;
            while(b[i]<threshold) {
                i++;
            }
            tim[j+1] = t[i];
            printf("t%d = %f\n",j+2,tim[j+1]);
            printf("instantaneous HR for the period %d = %f\n",j+1,60/(tim[j+1]-tim[j]));

        }
    }

    return 0;
}

[Tclausex]

The body of your code, at the end, where you're trying to find values in b over your threshold is outside of any loop construct. You'll only find the first instance of b[i] > threshold.

[BiomedOne]

The body of your code, at the end, where you're trying to find values in b over your threshold is outside of any loop construct. You'll only find the first instance of b[i] > threshold.

how would i go about reconstructing the bottom loop so the program continues to run throughout the data set? I attached the data set file we have to use with the program.

[Tclausex]

Well, you saved the last index to n after you read in the file contents. Surely you could make use of that in a while loop to evaluate the data and print your statements.