cachematrix.R

## Below are two functions that are used to create a
## special object that stores a numeric vector and caches its mean.

## The first function, `makeCacheMatrix` creates a special "vector", which is
## really a list containing a function to

## 1.  set the value of the vector
## 2.  get the value of the vector
## 3.  set the value of the inverse
## 4.  get the value of the inverse

makeCacheMatrix <- function(x = matrix()) {
		i <- NULL
		 	set <- function(y){
		 		x <<- y
		 		i <<- NULL
		 	}
		 	get <- function() x
		 	setinverse <- function(inverse) i <<- inverse
		 	getinverse <- function() i
		 	list(set = set, get = get, 
		 		setinverse = setinverse,
		 		getinverse = getinverse )
}


## The following function calculates the inverse of the special "vector"
## created with the above function. However, it first checks to see if the
## inverse has already been calculated. If so, it `get`s the inverse from the
## cache and skips the computation. Otherwise, it calculates the inverse of
## the data and sets the value of the inverse in the cache via the `setinverse`
## function.

cacheSolve <- function(x, ...) {
	i <- x$getinverse()
 	if(!is.null(i)){
 		message("getting cached data")
 		return(i)
 	}
 	data <- x$get()
 	i <- solve(data, ...)
 	x$setinverse(i)
 	i        ## Returns a matrix that is the inverse of 'x'
}