How to Get Largest and Smallest Element in 2D Array in Java Column Wise I Have Got Output for Row Wise

How to get largest and smallest element in 2d array in java column wise I have got output for row wise

Switch the order of the loops in order to find column wise minimum and maximum:

for (int col = 0; col < data[0].length; col++) { // assuming all row have same length

    int large = data[0][col], 
        small = data[0][col];

    for (int row = 1; row < data.length; row++) {
        if (large < data[row][col]) {
            large = data[row][col];

        }
        if (small > data[row][col]) {
            small = data[row][col];
        }

    }
    System.out.println("\nlargest values:" + large);
    System.out.println("smallest values:" +small);
}

Output:

largest values:9
smallest values:-10

largest values:6
smallest values:2

largest values:5
smallest values:-100

largest values:-2
smallest values:-45

Largest Row or Column in Matrix

You have almost gotten the solution, the only problem is that you are not resetting the sum1 and sum2 before calculating the sum of each row and column respectively. You should do it right before the second loop in each case.

Java: Compare elements of 2D array(matrix) in the column And finding row number containing smallest value in that column

First of all I think you are confused about row and column of an array. Your array has 3 rows and 4 columns. I will assume you want to find the column index of smallest element of each row. If so, find below code:

        double arr[][] = {{2, 3, 4, 6},
                {3, 6, 7.0, 3.3},
                {2.1, 3.4, 2, 7.7}
        };

        for (int i = 0; i < arr.length; i++) {
        int column = 0;
        for (int j = 1; j < arr[i].length; j++) {
            column = (arr[i][column] < arr[i][j]) ? column : j;
        }
        System.out.println("Smallest element for row " + i + " = " + column +" th column");
    }

Hope this helps ;)

Updated one(to find row number):

double arr[][] = {{2, 3, 4, 6},
                {3, 6, 7.0, 3.3},
                {2.1, 3.4, 2, 7.7}
        };


        for(int j=0;j<arr[0].length;j++)
        {
            int row = 0;
            for (int i = 1; i < arr.length; i++) {
                row = (arr[row][j] < arr[i][j]) ? row : i;
            }
            System.out.println("Column = " + j + " Row = " + row);
        }

Jagged array; check for column-wise value increase

This approach takes a row. It considers 'this' row and the one after it. It considers N number of columns, where N is the minimum of the number of columns in this row and the row after. In math, if R is the number of rows in this 2D matrix, take some r₁: r₁ ∈ [0, R) and r₂ = r₁ + 1. Then, N = min{num_cols(r₁), num_cols(r₂)}.

In column n, where n ∈ [0, N], if the value at the column in the next row happens to be smaller than the value in the preceding row, it returns false. If everything else worked, it returns true.

public static boolean columnValuesIncrease(int[][] t) {
    for(int i = 0 ; i < t.length - 1 ; i++) 
        for(int j = 0 ; j < Math.min(t[i].length, t[i+1].length) ; j++) 
            if(t[i][j] > t[i+1][j])
                return false;
    return true;
}

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