From 4d5a3df43383cc5173b6b67569ebd865e4346f6d Mon Sep 17 00:00:00 2001
From: Kwame <atokubi@gmail.com>
Date: Fri, 13 Mar 2015 18:45:52 +0000
Subject: [PATCH 1/2] cache matrix completed

---
 cachematrix.R | 21 ++++++++++++++++++++-
 1 file changed, 20 insertions(+), 1 deletion(-)

diff --git a/cachematrix.R b/cachematrix.R
index a50be65aa44..07a5c856182 100644
--- a/cachematrix.R
+++ b/cachematrix.R
@@ -4,7 +4,17 @@
 ## Write a short comment describing this function
 
 makeCacheMatrix <- function(x = matrix()) {
-
+        mi <- NULL
+        set <- function(y) {
+                x <<- y
+                mi <<- NULL
+        }
+        get <- function() x
+        setmatrix_inv <- function(solvex) mi <<- solvex
+        getmatrix_inv <- function() mi
+        list(set = set, get = get,
+             setmatrix_inv = setmatrix_inv,
+             getmatrix_inv = getmatrix_inv)
 }
 
 
@@ -12,4 +22,13 @@ makeCacheMatrix <- function(x = matrix()) {
 
 cacheSolve <- function(x, ...) {
         ## Return a matrix that is the inverse of 'x'
+        mi <- x$getmatrix_inv()
+        if(!is.null(mi)) {
+                message("getting cached data")
+                return(mi)
+        }
+        data <- x$get()
+        mi <- solve(data, ...)
+        x$setmatrix_inv(mi)
+        mi
 }

From b5375e377182bb6b4ca3eea540057a3a67c28fbe Mon Sep 17 00:00:00 2001
From: Kwame <atokubi@gmail.com>
Date: Fri, 13 Mar 2015 19:00:11 +0000
Subject: [PATCH 2/2] updated comments

---
 cachematrix.R | 13 ++++++-------
 1 file changed, 6 insertions(+), 7 deletions(-)

diff --git a/cachematrix.R b/cachematrix.R
index 07a5c856182..e01fa7be1a3 100644
--- a/cachematrix.R
+++ b/cachematrix.R
@@ -1,8 +1,8 @@
-## Put comments here that give an overall description of what your
-## functions do
-
-## Write a short comment describing this function
+## cacheSolve works objects created with makeCacheMatrix to 
+## store previously computed results of matrix inverses
 
+## makeCacheMatrix sets up a matrix object via a list 
+## to store itself and a cache of its inverse
 makeCacheMatrix <- function(x = matrix()) {
         mi <- NULL
         set <- function(y) {
@@ -17,9 +17,8 @@ makeCacheMatrix <- function(x = matrix()) {
              getmatrix_inv = getmatrix_inv)
 }
 
-
-## Write a short comment describing this function
-
+## cacheSolve first checks if the matrix's inverse has previously been 
+## computed and cached to be returned. Computes and cache the inverse otherwise.
 cacheSolve <- function(x, ...) {
         ## Return a matrix that is the inverse of 'x'
         mi <- x$getmatrix_inv()