how to print the average of each column of 2d n*m array using java

here is my code:

import java.io.File;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import java.util.Scanner;
public class ReadContents {
    public static void main(String[] args) throws IOException {
        File file = new File("file1.txt");
        List<float[]> list = new ArrayList<float[]>();
        Scanner scanner = new Scanner(file).useDelimiter("\n");
        while (scanner.hasNext()) {     
            String[] values = scanner.next().trim().split(" "); 
             float[] floats = new float[values.length];
             for (int i = 0; i < values.length; i++) {
                 floats[i] = Float.parseFloat(values[i]);
                 }
                 list.add(floats);
                 } 
                 float[][] values = new float[list.size()][];
                 for (int i = 0; i < list.size(); i++) {
                     values[i] = list.get(i);
                     for (int j = 0; j < values[i].length; j++) {
                         System.out.print(values[i][j] + " ");
                         }
                         System.out.println();
                 }

it prints the content of file.now i want to calculate mean(average) of each column present in the given file having say n*m matrix.