How to Calculate the Average of Each Row in Multidimensional Array

Trying to find the average of EACH row in a 2d array

A couple of corrections to two of the methods. See the code comments for further explanation:

public static int display2DArray(int[][] a2) {
    for (int row = 0; row < 3; row++){
        for (int column = 0; column < 4; column++){
            System.out.print(a2[row][column] + " "); // better display
        }
        System.out.println(); // better display
    }
    return 0;
}

and:

public static double averageRow(int[][] a2) {
    int rowTotal = 0;
    double average = 0;

    for (int row = 0; row < a2.length; row++){
        for (int column = 0; column < a2[row].length; column++){
            rowTotal += a2[row][column];
        }
        average = rowTotal / a2[row].length; // calc average
        System.out.println(average); // print the row average
        rowTotal = 0; // start over (for next row)
    }
    return rowTotal;
}

Output of averageRow:

25.0
65.0
105.0

How to calculate the average of each row in multidimensional array

You can do it something like this

for(int i = 0; i < 3; i++)
{
    int Avg = 0;
    for(int x = 0; x < 3; x++)
    {
        Console.Write(number[x, i] + " ");
        Avg += number[x, i];
    }
    Avg = Avg / 3;
    Console.Write("Average is" + Avg);
    Console.WriteLine(" ");
    Console.ReadLine();
}

Calculate the average of a row in a two dimensional array

You should create a sum while looping over each array:

public static void printtda() {

  int[][] temps = { {27,28,26,29,30}, {26,25,25,37,40} };

  for (int i=0; i<temps.length; i++) {
    int sum = 0;
    for (int g=0; g< temps[i].length; g++) {
        sum+=temps[i][g];
        System.out.print(temps[i][g] +"  ");
    }
    System.out.println(sum/temps[i].length);
    System.out.println();
  }   
}

How do I to print out the average of each row of a 2D array separately?

Not the best, but the easiest solution would be to simply change the type of sum to float or double

float sum = 0;

This will make the division that happens on the println to change from integer division to a floating point one, if only one of the operands has a floating point then your print will have a dot

Average of a row in a two-dimensional array in C?

Most errors were present in your dAvg function:

Namely:

1. You should not pass the entire 2D array if you only need one row there
2. You should pass the length of the array instead of hardcoding it everywhere (good practice, not a bug)
3. Your r was kept uninitialised therefore your indexing was not working
4. You were returning the average in every iteration therefore instead of summing the values you added the first and then you returned before adding the others.

double dAvg(double array[], size_t length){
    size_t c;
    double sum = 0;

    // Calculate sum first
    for (c = 0; c < length; c++){
        sum += array[c];
    }

    // Find average by dividing the sum by the number of numbers in a row
    return sum / (double) length;
} 

int main(void){
    int i;
    //Initiallize array
    double array[3][5] = {{3.0,5.0,2.0,1.0,0.0}, {4.0,8.0,6.0,3.0,3.0}, {7.0,6.0,2.0,3.0,5.0}};

    //Computes the average value per row of array
    for(i = 0; i < 3; i++){
        printf("The average of row %d is %f\n", i, dAvg(array[i], 5));
    }

    return 0;
}

Trying to get the average for each element in a two dimensional array

I would use List for this

public void studentAverage() throws FileNotFoundException {
    File infile= new File("qdata.txt");
    Scanner sc = new Scanner(infile);
    double rowNum = 0;
    List<List<Integer>> grades = new ArrayList<>();
    double totalCount = 0.0;
    while (sc.hasNext()) {
        List<Integer> row = new ArrayList<>();
        Scanner lineScanner= new Scanner(sc.nextLine());
        while (lineScanner.hasNextInt()) {
            row.add(lineScanner.nextInt());
        }
        grades.add(row);
        totalCount += row.size();
    }

    int index = 0;
    for (List<Integer> list : grades) {
        for (Integer grade : list) {
          System.out.println("Student average is " + (double)Math.round(grade.doubleValue() / totalCount * 10) / 10);
        }
    }
}

How to find a total average on a multidimensional array (java)

I would try nested for loops. Something like this..

int sum = 0;
int indexCounter = 0; // Use this to keep track of the number of 'entries' in the arrays since they may not be perfectly rectangular.
for(int column = 0; column < temps.length; column++) {
    for(int row = 0; row < temps[column].length; row++) {
        sum+= temps[column][row];
        indexCounter++;
    }
}
int average = sum / indexCounter;
System.out.println("The average is " + average);

If you knew for sure that each row had the same number of columns then you could do something like

 int average = sum / (temps.length * temps[0].length)

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