homework assignment solution

Author: Aaron Brady

cachematrix.R

@@ -1,15 +1,33 @@
 ## Put comments here that give an overall description of what your
 ## functions do
 
-## Write a short comment describing this function
-
+## Creates a matrix that will cache its inverse, a costly operation
 makeCacheMatrix <- function(x = matrix()) {
-
+  inv <- NULL
+  list(
+    set = function (y) {
+      x <<- y
+      inv <<- NULL
+    },
+    get    = function() x,
+    setInv = function(new_inv)  inv <<- new_inv,
+    getInv = function() inv
+  )
 }
 
-
-## Write a short comment describing this function
-
+# Find the inverse of the passed matrix and return it and cache it in the passed param 
+# note that x must be a value returned from 'makeCachedMatrix' 
+# The following function calculates the inverse of the special matrix
+# created with 'makeCachedMatrix' 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 inverse of
+# the matrix and sets the value using the setInv function on x
 cacheSolve <- function(x, ...) {
-        ## Return a matrix that is the inverse of 'x'
+  inv <- x$getInv()
+  if (!is.null(inv)) {
+    return(inv)
+  }
+  inv <- solve(x$get())
+  x$setInv(inv)
+  inv
 }