expands the makeCacheMatrixand cacheSolve functions

Author: swarnasras

cachematrix.R

@@ -2,14 +2,46 @@
 ## functions do
 
 ## Write a short comment describing this function
+###The first function, makeCacheMatrix creates a special "matrix"
+###which is really a list containing a function to
+###*set the value of the matrix
+###*get the value of the matrix
+###*set the value of the inverse
+###*get the value of the inverse
 
 makeCacheMatrix <- function(x = matrix()) {
-
+  m <- NULL
+  set <- function(y) {
+    x <<- y
+    m <<- NULL
+  }
+  get <- function() x
+  setinverse <- function(solve) m <<- solve
+  getinverse <- function() m
+  list(set = set, get = get,
+       setinverse = setinverse,
+       getinverse = getinverse) 
 }
 
 
 ## Write a short comment describing this function
+###The following function calculates the inverse of the 
+###special "matrix" created with the above function.
+###However, it first checks to see if the inverse has 
+###already been calculated. If so, it gets the inverse 
+###from the cache and skips the computation. 
+###Otherwise, it calculates the mean of the data and sets 
+###the value of the inverse in the cache via the setinverse function.
 
 cacheSolve <- function(x, ...) {
-        ## Return a matrix that is the inverse of 'x'
-}
+  ## Return a matrix that is the inverse of 'x'
+  m <- x$getinverse()
+  if(!is.null(m)) {
+    message("getting cached data")
+    return(m)
+  }
+  data <- x$get()
+  m <- solve(data, ...)
+  x$setinverse(m)
+  m
+}