*8.27 (Column sorting) Implement the following method to sort the columns in a two-
dimensional array. A new array is returned and the original array is intact.
public static double[][] sortColumns(double[][] m)
Write a test program that prompts the user to enter a 3 * 3 matrix of double values and displays a new column-sorted matrix. Here is a sample run:
Enter a 3-by-3 matrix row by row:
0.15 0.875 0.375
0.55 0.005 0.225
0.30 0.12 0.4
The column-sorted array is
0.15 0.0050 0.225
0.3 0.12 0.375
0.55 0.875 0.4
public static double[][] sortColumns(double[][] m)
Write a test program that prompts the user to enter a 3 * 3 matrix of double values and displays a new column-sorted matrix. Here is a sample run:
Enter a 3-by-3 matrix row by row:
0.15 0.875 0.375
0.55 0.005 0.225
0.30 0.12 0.4
The column-sorted array is
0.15 0.0050 0.225
0.3 0.12 0.375
0.55 0.875 0.4
import java.util.Scanner; public class ProgrammingEx8_27{ public static void main(String[] args) { Scanner input = new Scanner(System.in); System.out.println("Enter a 3-by-3 matrix row by row:"); double[][] n = new double[3][3]; for (int i = 0; i < n.length; i++) { for (int j = 0; j < n[i].length; j++) { n[i][j] = input.nextDouble(); } } double[][] sorted = sortColumns(n); System.out.println("The original array is:"); display(n); System.out.println("The row-sorted array is:"); display(sorted); } public static double[][] sortColumns(double[][] m) { double[][] result = new double[m.length][m[0].length]; double [] col = new double[m.length]; for (int i = 0; i < result.length; i++) { for (int j = 0; j < col.length; j++) { col[j] = m[j][i]; } col = selectionSort(col); for (int j = 0; j < col.length; j++) { result[j][i]=col[j]; } } return result; } public static double[] selectionSort(double[] inputList) { double[] list = inputList.clone(); for (int i = 0; i < list.length - 1; i++) { // Find the minimum in the list[i..list.length-1] double currentMin = list[i]; int currentMinIndex = i; for (int j = i + 1; j < list.length; j++) { if (currentMin > list[j]) { currentMin = list[j]; currentMinIndex = j; } } // Swap list[i] with list[currentMinIndex] if necessary if (currentMinIndex != i) { list[currentMinIndex] = list[i]; list[i] = currentMin; } } return list; } public static void display(double[][] list) { for (int i = 0; i < list.length; i++) { for (int j = 0; j < list.length; j++) { System.out.print(list[i][j] + " "); } System.out.println(); } } }
No comments :
Post a Comment