From 81c53e18ddeb1a81df710b2f98f0cd0c13975d8c Mon Sep 17 00:00:00 2001
From: Alexander McMurray <alexgmcm@gmail.com>
Date: Sun, 18 Jan 2015 18:25:26 +0000
Subject: [PATCH 1/2] Submitting solution

---
 cachematrix.R | 32 +++++++++++++++++++++++++-------
 1 file changed, 25 insertions(+), 7 deletions(-)

diff --git a/cachematrix.R b/cachematrix.R
index a50be65aa44..5c948fc4913 100644
--- a/cachematrix.R
+++ b/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
-
 makeCacheMatrix <- function(x = matrix()) {
-
+		#This function creates a special "matrix" object that can cache its inverse.
+		inverse<-NULL
+		set <- function(y){
+			x<<-y
+			inverse<<-NULL
+		}
+		get <- function() x
+		setinverse <- function(inv) inverse<<-inv
+		getinverse <- function() inverse
+		list(set=set, get=get, setinverse=setinverse, getinverse=getinverse)
 }
 
 
-## Write a short comment describing this function
 
 cacheSolve <- function(x, ...) {
         ## Return a matrix that is the inverse of 'x'
+        # 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 the cachesolve should retrieve the inverse from the cache.
+        inverse<-x$getinverse()
+        if(!is.null(inverse)){
+        	message("getting cached data")
+            return(inverse)
+        }
+        data<-x$get()
+        inverse<-solve(data, ...) 
+        #ellipses in case we want to pass additional arguments to solve()
+        #note the ellipses in the function def that implies this functionality
+        #is desired
+        x$setinverse(inverse) #set it for caching
+        inverse #return
 }

From ff93c1bd1abccf04cd931a2dbec1d2331ca43a99 Mon Sep 17 00:00:00 2001
From: Alexander McMurray <alexgmcm@gmail.com>
Date: Sun, 18 Jan 2015 18:32:48 +0000
Subject: [PATCH 2/2] Submitting solution2

---
 cachematrix.R | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/cachematrix.R b/cachematrix.R
index 5c948fc4913..5f43cf077e7 100644
--- a/cachematrix.R
+++ b/cachematrix.R
@@ -1,14 +1,16 @@
 makeCacheMatrix <- function(x = matrix()) {
 		#This function creates a special "matrix" object that can cache its inverse.
-		inverse<-NULL
+		inverse<-NULL 
 		set <- function(y){
 			x<<-y
-			inverse<<-NULL
+			inverse<<-NULL 
+			#this means if we change the matrix, we won't retain the old, now incorrect inverse
 		}
 		get <- function() x
 		setinverse <- function(inv) inverse<<-inv
 		getinverse <- function() inverse
-		list(set=set, get=get, setinverse=setinverse, getinverse=getinverse)
+		#return list of functions
+		list(set=set, get=get, setinverse=setinverse, getinverse=getinverse) 
 }