Inverse of matrix

Author: awad

cachematrix.R

@@ -1,15 +1,37 @@
 ## Put comments here that give an overall description of what your
 ## functions do
 
-## Write a short comment describing this function
-
+## This function creates a special "matrix" object
+## that can cache its inverse.
 makeCacheMatrix <- function(x = matrix()) {
-
+  inv <- NULL
+  set <- function(y) {
+    x <<- y
+    inv <<- NULL
+  }
+  get <- function() x
+  setinverse <- function(inverse) inv <<- inverse
+  getinverse <- function() inv
+  
+  list(set = set, get = get,
+       setinverse = setinverse,
+       getinverse = getinverse)
 }
 
 
-## Write a short comment describing this function
-
+## 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
+##this function` retrieves the inverse from the cache.
 cacheSolve <- function(x, ...) {
-        ## Return a matrix that is the inverse of 'x'
-}
+  ## Return a matrix that is the inverse of 'x'
+  inv <- x$getinverse()
+  if(!is.null(inv)) {
+    message("getting cached data")
+    return(inv)
+  }
+  data <- x$get()
+  inv <- solve(data, ...)
+  x$setinverse(inv)
+  inv        
+}