This is the java program to find the inverse of square invertible matrix. The matrix is invertible if its determinant is non zero.
Here is the source code of the Java Program to Find Inverse of a Matrix. The Java program is successfully compiled and run on a Windows system. The program output is also shown below.
//This is sample program to find the inverse of a matrix import java.util.Scanner; public class Inverse { public static void main(String argv[]) { Scanner input = new Scanner(System.in); System.out.println("Enter the dimension of square matrix: "); int n = input.nextInt(); double a[][]= new double[n][n]; System.out.println("Enter the elements of matrix: "); for(int i=0; i<n; i++) for(int j=0; j<n; j++) a[i][j] = input.nextDouble(); double d[][] = invert(a); System.out.println("The inverse is: "); for (int i=0; i<n; ++i) { for (int j=0; j<n; ++j) { System.out.print(d[i][j]+" "); } System.out.println(); } input.close(); } public static double[][] invert(double a[][]) { int n = a.length; double x[][] = new double[n][n]; double b[][] = new double[n][n]; int index[] = new int[n]; for (int i=0; i<n; ++i) b[i][i] = 1; // Transform the matrix into an upper triangle gaussian(a, index); // Update the matrix b[i][j] with the ratios stored for (int i=0; i<n-1; ++i) for (int j=i+1; j<n; ++j) for (int k=0; k<n; ++k) b[index[j]][k] -= a[index[j]][i]*b[index[i]][k]; // Perform backward substitutions for (int i=0; i<n; ++i) { x[n-1][i] = b[index[n-1]][i]/a[index[n-1]][n-1]; for (int j=n-2; j>=0; --j) { x[j][i] = b[index[j]][i]; for (int k=j+1; k<n; ++k) { x[j][i] -= a[index[j]][k]*x[k][i]; } x[j][i] /= a[index[j]][j]; } } return x; } // Method to carry out the partial-pivoting Gaussian // elimination. Here index[] stores pivoting order. public static void gaussian(double a[][], int index[]) { int n = index.length; double c[] = new double[n]; // Initialize the index for (int i=0; i<n; ++i) index[i] = i; // Find the rescaling factors, one from each row for (int i=0; i<n; ++i) { double c1 = 0; for (int j=0; j<n; ++j) { double c0 = Math.abs(a[i][j]); if (c0 > c1) c1 = c0; } c[i] = c1; } // Search the pivoting element from each column int k = 0; for (int j=0; j<n-1; ++j) { double pi1 = 0; for (int i=j; i<n; ++i) { double pi0 = Math.abs(a[index[i]][j]); pi0 /= c[index[i]]; if (pi0 > pi1) { pi1 = pi0; k = i; } } // Interchange rows according to the pivoting order int itmp = index[j]; index[j] = index[k]; index[k] = itmp; for (int i=j+1; i<n; ++i) { double pj = a[index[i]][j]/a[index[j]][j]; // Record pivoting ratios below the diagonal a[index[i]][j] = pj; // Modify other elements accordingly for (int l=j+1; l<n; ++l) a[index[i]][l] -= pj*a[index[j]][l]; } } } }
Output:
$ javac Inverse.java $ java Inverse Enter the dimension of square matrix: 2 Enter the elements of matrix: 1 2 3 4 The Inverse is: -1.9999999999999998 1.0 1.4999999999999998 -0.49999999999999994
Related posts:
Java Program to Evaluate an Expression using Stacks
Java Program to Implement Max Heap
Java Timer
Hướng dẫn tạo và sử dụng ThreadPool trong Java
Java Program to Implement AA Tree
@DynamicUpdate with Spring Data JPA
Spring Boot: Customize Whitelabel Error Page
Using Spring @ResponseStatus to Set HTTP Status Code
Spring Boot - Code Structure
Check if there is mail waiting
Java Program to Implement Knight’s Tour Problem
Jackson Ignore Properties on Marshalling
Intro to Spring Boot Starters
Java Program to implement Priority Queue
Introduction to Spring Security Expressions
How to Replace Many if Statements in Java
Java Program to Perform Postorder Recursive Traversal of a Given Binary Tree
Java Program to Delete a Particular Node in a Tree Without Using Recursion
Java Program to Implement Hash Tables Chaining with Doubly Linked Lists
Java Program to Apply Above-Below-on Test to Find the Position of a Point with respect to a Line
How to Get the Last Element of a Stream in Java?
Java Program to Implement Floyd-Warshall Algorithm
Custom HTTP Header with the HttpClient
Ways to Iterate Over a List in Java
Java Program to Generate All Pairs of Subsets Whose Union Make the Set
Java Program to Implement Double Order Traversal of a Binary Tree
Sorting Query Results with Spring Data
Java Program to Implement Pollard Rho Algorithm
Hướng dẫn sử dụng Java Annotation
Java Program to Implement Sparse Array
Mix plain text and HTML content in a mail
Default Password Encoder in Spring Security 5