From e1f23daedc5ef9f5b1976e9d73ba808e457eb132 Mon Sep 17 00:00:00 2001
From: Joel M <me@joelmahatsri.com>
Date: Sat, 19 Mar 2016 13:41:45 +0000
Subject: [PATCH 1/3] Initial Commit.

---
 cachematrix.R | 46 ++++++++++++++++++++++++++++++++++++++--------
 1 file changed, 38 insertions(+), 8 deletions(-)

diff --git a/cachematrix.R b/cachematrix.R
index a50be65aa44..f05ed77d8e7 100644
--- a/cachematrix.R
+++ b/cachematrix.R
@@ -1,15 +1,45 @@
-## Put comments here that give an overall description of what your
-## functions do
-
-## Write a short comment describing this function
+## cachematrix() contains convenience functions for 
+## matrix storage and inversion. The matirx 'x' will have 
+## its inverse calculated once. If the inverse has already 
+## been calculated (and the matrix has not changed), then 
+## the cachesolve() should retrieve the inverse from the cache.
 
+## This function creates a special "matrix" object 
+## that can cache its inverse
 makeCacheMatrix <- function(x = matrix()) {
-
+    im <- NULL
+    
+    set <- function(y){
+        x <- y
+        im <<- NULL
+    }
+   
+    get <- function() x
+    setmatrix <- function(solve) im <<- solve
+    getmatrix <- function() im
+    
+    list( set=set, get=get, 
+          setmatrix=setmatrix,
+          getmatrix=getmatrix)
 }
 
 
-## Write a short comment describing this function
-
+## 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.
 cacheSolve <- function(x, ...) {
-        ## Return a matrix that is the inverse of 'x'
+    ## This function assume that the matrix supplied is 
+    ## always invertible.
+    im <- x$getmatrix()
+    if(!is.null(im)){
+        message("getting cached data...")
+        return (im)
+    }
+    m <- x$get()
+    im <- solve(m, ...)
+    x$setmatrix(im)
+    ## Return a matrix that is the inverse of 'x'
+    im
 }

From 0d22d72b84364958752432b0bb82b1a870bcbba8 Mon Sep 17 00:00:00 2001
From: Joel M <me@joelmahatsri.com>
Date: Sat, 19 Mar 2016 13:53:58 +0000
Subject: [PATCH 2/3] tidy up..

---
 cachematrix.R | 1 -
 1 file changed, 1 deletion(-)

diff --git a/cachematrix.R b/cachematrix.R
index f05ed77d8e7..0101d2f46ac 100644
--- a/cachematrix.R
+++ b/cachematrix.R
@@ -34,7 +34,6 @@ cacheSolve <- function(x, ...) {
     ## always invertible.
     im <- x$getmatrix()
     if(!is.null(im)){
-        message("getting cached data...")
         return (im)
     }
     m <- x$get()

From be9d12453f1803cbe650dd3b08dc4b7e8c37f4fd Mon Sep 17 00:00:00 2001
From: Joel M <me@joelmahatsri.com>
Date: Sat, 19 Mar 2016 19:12:50 +0000
Subject: [PATCH 3/3] final revision

---
 cachematrix.R | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/cachematrix.R b/cachematrix.R
index 0101d2f46ac..2d64a90c1df 100644
--- a/cachematrix.R
+++ b/cachematrix.R
@@ -32,13 +32,16 @@ makeCacheMatrix <- function(x = matrix()) {
 cacheSolve <- function(x, ...) {
     ## This function assume that the matrix supplied is 
     ## always invertible.
+    
     im <- x$getmatrix()
     if(!is.null(im)){
+        message("Getting cached data..")
         return (im)
     }
-    m <- x$get()
+    m <- x$get() 
     im <- solve(m, ...)
     x$setmatrix(im)
+    
     ## Return a matrix that is the inverse of 'x'
     im
 }