function receive the array as a pointers

[poorman]

Hello:

My question is why my average are all 43.6
How to fix it?
Thank

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

#define ROW 3
#define COL 6

void openFile(int [][COL]);
void average (int [][COL], double *);
void report(int [][COL], double);

int main(void)
{
int table[ROW][COL];
double avg;

openFile(table);
average (table, &avg);
report(table, avg);

return 0;
}
/**************************** OPEN FILE *************/

void openFile(int table[][COL])
{
FILE *fp;

int row=0;

if(!(fp=fopen("ss.txt", "r")))
{
printf("\nCANNOT opening file ss.txt\n");
exit(EXIT_FAILURE);
}

while(fscanf(fp, "%d%d%d%d%d%d", &table[row][0], &table[row][1], &table[row][2],
&table[row][3], &table[row][4], &table[row][5]
)==6)

{row++;}

fclose(fp);
}

/******* average *********/

void average(int table[][COL], double *avg)
{
int row, col;

for(row=0; row<ROW; row++)
{
double tot=0;

for(col=1; col<COL; col++)
tot += *(*(table + row)+col);

*avg = tot / 5.0;
}
return;
}

/**************REPORT **************/

void report(int table[][COL], double avg)
{
int row, col;

for(row=0; row<ROW; row++)
{
printf("%4d", *(*(table+row)+0));

for(col=1; col<COL; col++)
{
printf("%10d", *(*(table + row)+col));
}
printf("%10.2lf\n", avg);
}

return;
}

1111 92 87 100 10 20 43.60
2222 50 63 48 36 10 43.60
3333 20 55 57 47 25 43.60

[foniks munkee]

It is to do with the way you are calling these three functions from main().

openFile(table);            // You read the data in this func.
average (table, &avg); // You perform the averages calculation
report(table, avg);       // You print out the report on screen

You have evaluated three averages, each time storing the data in double avg. So the first time you evaluate the average, avg is equal to a number. But you overwrite that value with the next iteration of the loop.
The reason that you have the same data three times is that you are trashing the data stored in avg each time you evaluate avg. You then pass the final value that was evaluated to report().

To fix this program you could do one of a couple of things. Have the average function only evaluate the average of one line of data every time. Then loop between average(); and report(); i.e. you print out the data to screen every time you evaluate one line of data.

or perhaps make avg an array. Store the results in a different element as you loop through your calculations.