Sort array method...

Question

Hi all,
I have a float array of many rows and two columns.
I was wondering whether it is possible to sort this array with calls of java api, just be specifing the column index number.
Thank you.

Answer 1

That works with Arrays.sort and Comparator
import java.util.*;
class FloatArray {
public static void main(String[] args){
Random rand=new Random();
float[][] floatArray=new float[10][2];
// filling the array with random numbers
for(int i=0; i<10; i++)
    for(int j=0; j<2; j++) {
        floatArray[i][j]=rand.nextFloat();
// sorting the first column
Arrays.sort(floatArray, new Comparator<float[]>() {
    public int compare(float[] f1, float[] f2)  {
        if (f1[0]>f2[0]) return 1;
        else if (f1[0]==f2[0]) return 0;
        else return -1;
for(int i=0; i<10; i++) {
    for(int j=0; j<2; j++) {
        System.out.print(floatArray[i][j]+", ");
    System.out.println();
System.out.println();
System.out.println();
// sorting the second column
Arrays.sort(floatArray, new Comparator<float[]>() {
    public int compare(float[] f1, float[] f2)  {
        if (f1[1]>f2[1]) return 1;
        else if (f1[1]==f2[1]) return 0;
        else return -1;
for(int i=0; i<10; i++) {
    for(int j=0; j<2; j++) {
        System.out.print(floatArray[i][j]+", ");
    System.out.println();
}