Thread: Complicated Condition

Hi. I have a problem that I could not figure out. I have these datasets read from a textfile (1 to N):

a1 b1
a2 b2
a3 b3
:
:
aN bN

I need to make this:

If 'a' have the same value, calculate the average of 'b'.
E.g: if a1 & a3 are the same value, than calculate (b1+b3)/2
or if a1=a3=a4=a10, then calculate the average of (b1+b3+b4+b10)/4

Thanks.Hope somebody out there can give me some ideas on this.

zmi

What's your best idea?

Originally Posted by Daved

What's your best idea?

I set the 'a' value and set a condition.But, this only calculate the average for the particular condition only.E.g: If I set a==60,then it will print average of 'b' if a==60. It did not work if there is multiple condition.
p/s: 'a' actually is the angle between 0 to 90 degrees.
Here is the sample of the code:

Code:

for(i=0;i<n;i++){
fscanf(fin,"%f,%f\n",&a[i],&b[i]);
}

for(i=0;i<n;i++){

if (a[i]==60){
     k=k+1;
    sum=sum+b[i];
    }
}
printf("%.1f\n",sum/k);

or something like this:

Code:

while (!feof(fin)){
     fscanf(fin,"%f,%f\n",&a,&b);

    if (a==60){
    sum=sum+b;
    k=k+1;
    printf("%.1f\n",sum/k);
    }

    }

Thank you for the idea.I managed to sort the data. Now I'm having trouble to calculate the average of 'b' (sum/k).
I got the sum, but don't know how to calculate the k value.

Here's the code to calculate the sum:

Code:

for(i=0; i<n; i++){

            for(j=i+1; j<n; j++){

                if(a[i] == a[j])
                {
                 k=k+1;
                 sum[i]=b[i]+b[j];
                 }

             }
             printf("%.1f %.3f %.1f %d\n",a[i],b[i],sum[i],k);
            }

This is sample of dataset I used (a,b):

60,10
70,11
80,20
60,25
70,30
60,14
80,20

This is the output (a,b,sum,k):

60.0 10.000 24.0 1
60.0 25.000 39.0 2
60.0 14.000 0.0 2
70.0 30.000 41.0 3
70.0 11.000 0.0 3
80.0 20.000 40.0 4
80.0 20.000 0.0 4