From 4e1e61b0dcd17edaa78588b2ea1d22dc95d00940 Mon Sep 17 00:00:00 2001
From: Evan Jehu <evan.jehu@gmail.com>
Date: Thu, 17 Jul 2014 21:41:58 -0400
Subject: [PATCH 1/3] initial version

---
 cachematrix.R | 53 ++++++++++++++++++++++++++++++++++++++++++---------
 1 file changed, 44 insertions(+), 9 deletions(-)

diff --git a/cachematrix.R b/cachematrix.R
index a50be65aa44..d9f7e648245 100644
--- a/cachematrix.R
+++ b/cachematrix.R
@@ -1,15 +1,50 @@
-## Put comments here that give an overall description of what your
-## functions do
-
-## Write a short comment describing this function
-
-makeCacheMatrix <- function(x = matrix()) {
+## A pair of functions that combined can create an object wrapping a square
+## matrix that can cache its inverse to avoid the expense of this operation
+## executing more than once.
 
+## 'matrix_val' is a square matrix to be contained in the cache enabled object.
+##
+## Return an object that contains the input martix_val with the ability to
+## cache its inverse.
+##
+makeCacheMatrix <- function(matrix_val = matrix()) {
+  inverse_val <- NULL
+  set <- function(new_matrix) {
+    matrix_val <<- new_matrix
+    inverse_val <<- NULL
+  }
+  get <- function() {
+    matrix_val
+  }
+  setInverse <- function(updated) {
+    inverse_val <<- updated
+  }
+  getInverse <- function() {
+    inverse_val
+  }
+  list(set = set,
+    get = get,
+    setInverse = setInverse,
+    getInverse = getInverse)
 }
 
 
-## Write a short comment describing this function
-
+## 'x' the cache matrix object created by a call to makeCacheMatrix.
+## '...' any optional arguments that should be passed to the call to solve()
+##        used to invert the contained matrix.
+##
+## Return the inverted matrix value, this will be calculated on the first call
+## but the result will be stored in the matrix object for later use.
+##
 cacheSolve <- function(x, ...) {
-        ## Return a matrix that is the inverse of 'x'
+  ## Return a matrix that is the inverse of 'x'
+  m <- x$getInverse()
+  if(is.null(m)) {
+    data <- x$get()
+    m <- solve(data, ...)
+    x$setInverse(m)
+  } else {
+    message("getting cached data")
+  }
+  m
 }

From eca794ad1a4dd25c9b7b5a91fdad7eeec8b5a63c Mon Sep 17 00:00:00 2001
From: Evan Jehu <evan.jehu@gmail.com>
Date: Thu, 17 Jul 2014 21:55:37 -0400
Subject: [PATCH 2/3] increased tab sizes from 2 to 4

---
 cachematrix.R | 56 +++++++++++++++++++++++++--------------------------
 1 file changed, 28 insertions(+), 28 deletions(-)

diff --git a/cachematrix.R b/cachematrix.R
index d9f7e648245..4e0dbedb00e 100644
--- a/cachematrix.R
+++ b/cachematrix.R
@@ -8,24 +8,24 @@
 ## cache its inverse.
 ##
 makeCacheMatrix <- function(matrix_val = matrix()) {
-  inverse_val <- NULL
-  set <- function(new_matrix) {
-    matrix_val <<- new_matrix
-    inverse_val <<- NULL
-  }
-  get <- function() {
-    matrix_val
-  }
-  setInverse <- function(updated) {
-    inverse_val <<- updated
-  }
-  getInverse <- function() {
-    inverse_val
-  }
-  list(set = set,
-    get = get,
-    setInverse = setInverse,
-    getInverse = getInverse)
+    inverse_val <- NULL
+    set <- function(new_matrix) {
+        matrix_val <<- new_matrix
+        inverse_val <<- NULL
+    }
+    get <- function() {
+        matrix_val
+    }
+    setInverse <- function(updated) {
+        inverse_val <<- updated
+    }
+    getInverse <- function() {
+        inverse_val
+    }
+    list(set = set,
+        get = get,
+        setInverse = setInverse,
+        getInverse = getInverse)
 }
 
 
@@ -37,14 +37,14 @@ makeCacheMatrix <- function(matrix_val = matrix()) {
 ## but the result will be stored in the matrix object for later use.
 ##
 cacheSolve <- function(x, ...) {
-  ## Return a matrix that is the inverse of 'x'
-  m <- x$getInverse()
-  if(is.null(m)) {
-    data <- x$get()
-    m <- solve(data, ...)
-    x$setInverse(m)
-  } else {
-    message("getting cached data")
-  }
-  m
+    ## Return a matrix that is the inverse of 'x'
+    m <- x$getInverse()
+    if(is.null(m)) {
+        data <- x$get()
+        m <- solve(data, ...)
+        x$setInverse(m)
+    } else {
+        message("getting cached data")
+    }
+    m
 }

From d60b8beb4bc4d49a04e594444f0c2eb8b32e7232 Mon Sep 17 00:00:00 2001
From: Evan Jehu <evan.jehu@gmail.com>
Date: Sun, 27 Jul 2014 09:51:39 -0400
Subject: [PATCH 3/3] comment improvement

---
 cachematrix.R | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/cachematrix.R b/cachematrix.R
index 4e0dbedb00e..e53777b2dc6 100644
--- a/cachematrix.R
+++ b/cachematrix.R
@@ -2,7 +2,8 @@
 ## matrix that can cache its inverse to avoid the expense of this operation
 ## executing more than once.
 
-## 'matrix_val' is a square matrix to be contained in the cache enabled object.
+## 'matrix_val' is a square matrix to be contained in the cache enabled object,
+## this function assumes that the matrix supplied is always invertible.
 ##
 ## Return an object that contains the input martix_val with the ability to
 ## cache its inverse.