here is code:

import java.io.File; import java.io.IOException; import java.util.ArrayList; import java.util.List; import java.util.Scanner; public class mat1 { public static void main(String[] args) throws IOException { Scanner s = new Scanner(new File("rfg.txt")); List list = new ArrayList(); while (s.hasNextLine()) { String line[] = s.nextLine().split(" ");

     list.add(new double[] { Double.parseDouble(line[0]),Double.parseDouble(line[1]),Double.parseDouble(line[2]),Double.parseDouble(line[3]) });
}
    int numberOfRows = list.size();
    int numberOfColumns =4; 
    double[][] floatValues = new double[numberOfRows][numberOfColumns];
    for (int i = 0; i < numberOfRows; i++) {
        for(int j=0;j<numberOfColumns;j++){
        floatValues[i] = list.get(i);
        System.out.print(floatValues[i][j] + " "/* + floatValues[i][1] + " " + floatValues[i][2]*/);

        }
        System.out.println();
    }

}}

here is .txt file:

1.0 3.1 2.1 3.4 2.4 2.0 4.6 5.1 0.2 3.3 4.7 9.1 4.0 5.4 5.1 3.2 6.1 2.1 6.4 2.6

here in program i have to specify no. of columns every time. it is not the case. but i want to print the file of any dimensions in the form of 2d n*m matrix. pls help me