From c59d125110ff701e6d4435c76a76b0c83a608071 Mon Sep 17 00:00:00 2001
From: Ojasva Jain <44553464+ojasva@users.noreply.github.com>
Date: Mon, 25 Oct 2021 10:57:21 +0530
Subject: [PATCH] Add Sparcity of a Matrix [Hacktoberfest] (#2659)

---
 Misc/Sparcity.java | 47 ++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 47 insertions(+)
 create mode 100644 Misc/Sparcity.java

diff --git a/Misc/Sparcity.java b/Misc/Sparcity.java
new file mode 100644
index 000000000..a14dc05e8
--- /dev/null
+++ b/Misc/Sparcity.java
@@ -0,0 +1,47 @@
+package Misc;
+import java.util.*;
+/*
+*A matrix is sparse if many of its coefficients are zero (In general if 2/3rd of matrix elements are 0, it is considered as sparse). 
+*The interest in sparsity arises because its exploitation can lead to enormous computational savings and because many large matrix problems that occur in practice are sparse.
+*
+* @author Ojasva Jain
+*/
+
+class Sparcity{
+    /*
+    * @return Sparcity of matrix
+    * 
+    * where sparcity = number of zeroes/total elements in matrix
+    *
+    */
+    static double sparcity(double [][] mat){
+        int zero =0;
+        //Traversing the matrix to count number of zeroes 
+        for(int i=0;i<mat.length;i++){
+            for(int j=0;j<mat[i].length;j++){
+                if(mat[i][j]==0)
+                zero++;
+            }
+        }
+        //return sparcity
+        return ((double)zero/(mat.length*mat[1].length));
+    }
+
+    //Driver method
+    public static void main(String [] args){
+        Scanner in = new Scanner(System.in);
+        System.out.println("Enter number of rows in matrix: ");
+        int n = in.nextInt();
+        System.out.println("Enter number of Columns in matrix: ");
+        int m = in.nextInt();
+
+        System.out.println("Enter Matrix elements: ");
+        double [][] mat = new double[n][m];
+        for(int i=0;i<n;i++){
+            for(int j=0;j<m;j++){
+                mat[i][j] = in.nextDouble();
+            }
+        }
+        System.out.println("Sparcity of matrix is: "+ sparcity(mat));
+    }
+}