Merge pull request rdpeng#1 from ganeshsimat/ganeshsimat-patch-1

Update cachematrix.R

Author: ganeshsimat

cachematrix.R

@@ -1,9 +1,24 @@
-## Put comments here that give an overall description of what your
-## functions do
+## makeCacheMatrix: This function creates a special "matrix" object that can cache its inverse
 
-## Write a short comment describing this function
+## cacheSolve: This function computes the inverse of the special "matrix" returned by makeCacheMatrix above. 
+## If the inverse has already been calculated (and the matrix has not changed), then the cachesolve should retrieve
+## the inverse from the cache
+
+## Computing the inverse of a square matrix can be done with the solve function in R.
+## For example, if X is a square invertible matrix, then solve(X) returns its inverse.
 
 makeCacheMatrix <- function(x = matrix()) {
+  I <- NULL
+  set <- function(y) {
+    x <<- y
+    I <<- NULL
+  }
+  get <- function() x
+  setinverse <- function(solve) I <<- solve
+  getinverse <- function() I
+  list(set = set, get = get,
+       setinverse = setinverse,
+       getinverse = getinverse)
 
 }
 
@@ -12,4 +27,13 @@ makeCacheMatrix <- function(x = matrix()) {
 
 cacheSolve <- function(x, ...) {
         ## Return a matrix that is the inverse of 'x'
+        I <- x$getinverse()
+        if(!is.null(I)) {
+            message("getting cached data")
+        return(I)
+      }
+      data <- x$get()
+      I <- solve(data, ...)
+  x$setinverse(I)
+  I
 }