Reading txt file into 2d array C++

Question

I know this question has been asked before, but I cannot seem to find an answer to my particular problem. I am reading in txt file.

weather.txt

1 52 32

2 54 32

3 54 30

4 48 28

5 37 25

6 37 25

7 46 34

8 55 45

9 59 46

10 61 37

11 55 32

12 59 34

There is more data but for space sake I put this.

I am trying to read into the array 0,0 1,0 2,0 then it will go to 0,1 1,1 2,1 then 0,2 1,2 2,2. Just repeating the rows. With the code I have now it just gets stuck. and the output looks like this....

Location: 0 : 0 Data in textFile: 1 Location: 1 : 0 Data in textFile: 1 Location: 2 : 0 Data in textFile: 1 Location: 0 : 1 Data in textFile: 1 Location: 1 : 1 Data in textFile: 1 Location: 2 : 1 Data in textFile: 1 Location: 0 : 2 Data in textFile: 1 Location: 1 : 2 Data in textFile: 1 Location: 2 : 2 Data in textFile: 1 Location: 0 : 3 Data in textFile: 1 Location: 1 : 3 Data in textFile: 1 Location: 2 : 3 Data in textFile: 1 Location: 0 : 4 Data in textFile: 1 Location: 1 : 4 Data in textFile: 1 Location: 2 : 4 Data in textFile: 1 Location: 0 : 5 Data in textFile: 1 Location: 1 : 5 Data in textFile: 1 Location: 2 : 5 Data in textFile: 1 Location: 0 : 6 Data in textFile: 1 Location: 1 : 6 Data in textFile: 1 Location: 2 : 6 Data in textFile: 1 Location: 0 : 7 Data in textFile: 1 Location: 1 : 7 Data in textFile: 1 Location: 2 : 7 Data in textFile: 1 Location: 0 : 8 Data in textFile: 1 Location: 1 : 8 Data in textFile: 1 Location: 2 : 8 Data in textFile: 1 Location: 0 : 9 Data in textFile: 1 Location: 1 : 9 Data in textFile: 1 Location: 2 : 9 Data in textFile: 1 Location: 0 : 10 Data in textFile: 1 Location: 1 : 10 Data in textFile: 1

It goes through the whole file but restarting back to 0,0.

Location: 0 : 0 Data in textFile: 52

Location: 1 : 0 Data in textFile: 52

Location: 2 : 0 Data in textFile: 52

Any help would be appreciated sorry for all the text just trying to be as clear as possible.

#include <iostream>
#include <fstream>

using namespace std;

int main() {

int width = 31;//declaring days or columns for array
int height = 3;//declaring information day and high and low
int data;

/* Code to read in txt file */
ifstream infile;
infile.open("weather.txt");

if (!infile) {
    cerr << "Unable to open file  C\n";
    exit(1);   // call system to stop
}
/* end code read text file */

 int tempDay[height][width];

  //PROBLEM WITH LOOP//
while (infile >> data) {
    for (int i = 0; i < width; ++i) {
        for (int j = 0; j < height ; ++j) {
        tempDay[j][i] = data;
 cout << "Location: " << j <<" : " << i << " Data in textFile: " <<data<<endl;
        }
     }

}

infile.close();
return 0;     
}

Answer 1

The following should work provided the text file is as described and there are any unexpected characters. It is similar to your code except it checks for an unexpected end-of-file (i.e. if there aren't WIDTH rows in the file) within the for loop.

#include <iostream>
#include <fstream>
#include <cstdlib>

using namespace std;

int main() {

const int WIDTH = 31;//declaring days or columns for array
const int HEIGHT = 3;//declaring information day and high and low

/* Code to read in txt file */
ifstream infile;
infile.open("weather.txt");

if (!infile) {
    cerr << "Unable to open file\n" << endl;
    exit(1);   // call system to stop
}
/* end code read text file */

int tempDay[HEIGHT][WIDTH];

for (int i = 0; i < WIDTH; ++i) {
    for (int j = 0; j < HEIGHT ; ++j) {
        if (!(infile >> tempDay[j][i])) {
            cerr << "Unexpected end of file\n" << endl;
            exit(1);   // call system to stop
        }
        cout << "Location: " << j <<" : " << i << " Data in textFile: " << tempDay[j][i] << endl;
    }
}

infile.close();
return 0;     
}

Answer 2

Since you know the sizes, this should work:

const int width = 3;//declaring days or columns for array
const int height = 31;//declaring information day and high and low

// .. 

int tempDay[height][width];

// ..

int i = 0;
while (infile >> tempDay[i][0] >> tempDay[i][1] >> tempDay[i][2]) // one line at a time
{
    cout << tempDay[i][0] << ' ' << tempDay[i][1] << ' ' << tempDay[i][2] << endl;
    i++;
}