Thread: Help with matrix reading from a file

Hello I am having trouble to get desired output for reading a 3x3 matrix from a data file
The code is::
insert

Code:

    FILE *arr;
    float k[3][3]={0.0};
    arr =fopen("data11.txt","r");
    int i,j;
    for(i=0 ;i<3; i++)
        for(j=0; j<3; j++)
        {
            fscanf(arr, "%f%*[^\n]%*c",&k[i][j]);
            printf("%f\n", k[i][j]);
        }

and data file is::
0 5 10 54 57 58 90 45
2 0 15 1 12 12 0 84
1 3 0 87 48 0 45 9
4 58 4 0 84 95 78 12

output should be ::
0 5 10
2 0 15
1 3 0

instead its showing::
0 5 10
54 57 58
90 45 2

whats the problem here? I am a novice in programming so if anyone can help I would much appriciate it.Thanks in advance.

Your question is extremely deceptive since you've invented data that you didn't actually use. Your actual data file is more like this:

Code:

1 2 3 4 5 6
2 ...
3 ...
4 ...
5 ...
6 ...

I.e., it has the same values going down the first column as are in the first row.
Your program is simply reading the first value from each row, as per your fscanf format.
If you want to read the first three, try:

Code:

    for (i = 0; i < 3; i++)
        fscanf(arr, "%f%f%f%*[^\n]%*c", &k[i][0], &k[i][1], &k[i][2]);

Or

Code:

    for (i = 0; i < 3; i++) {
        for (j = 0; j < 3; j++) {
            fscanf(arr, "%f", &k[i][j]);
        }
        fscanf(arr, "%*[^\n]%*c");
    }

Originally Posted by Salem

Given your input file consists only of numbers, with whitespace and newlines, you can dispense with the "%*[^\n]%*c" parts.

My understanding is that he only wants to read a certain number of values (e.g., 3) from each line and skip the rest of the line.