cachematrix script

cachematrix.R

@@ -1,15 +1,40 @@
-## Put comments here that give an overall description of what your
-## functions do
+## The following two functions find the inverse of a matrix.  
+## If the matrix has already been inverted by cacheSolve, then 
+## the solution is retrieved from cached values. 
 
-## Write a short comment describing this function
+## makeCacheMatrix sets the value of the matrix, gets the value of the matrix, 
+## sets the inverse of the matrix and gets the inverse of the matrix. The 
+## function then makes a list of 4 functions: set, get, getinverse, and setinverse.
 
 makeCacheMatrix <- function(x = matrix()) {
-
+        invert <- NULL
+        set <- function(y) {
+                x <<- y
+                invert <<- NULL
+        }
+        get <- function() x
+        setinverse <- function(inverse) invert <<- inverse
+        getinverse <- function() invert
+        list(set = set, get = get,
+             setinverse = setinverse, 
+             getinverse = getinverse)
 }
 
 
-## Write a short comment describing this function
+## cacheSolve returns the inverse of a matrix.  If the matrix has already 
+## been inverted by these functions, it returns the cached solution.  If 
+## the input is a unique matrix cacheSolve solves for the inverse of the 
+## matrix.
 
 cacheSolve <- function(x, ...) {
         ## Return a matrix that is the inverse of 'x'
-}
+        invert <- x$getinverse()
+        if(!is.null(invert)) {
+                message("getting cached data")
+                return(invert)
+        }
+        data <- x$get()
+        invert <- solve(data, ...)
+        x$setinverse(invert)
+        invert
+}