1- # # Put comments here that give an overall description of what your
2- # # functions do
1+ # # OVERALL DESCRIPTION:
2+
3+ # # These are two methods that will store an inputted
4+ # # matrix into the cache and calculate it's inverse.
5+ # # This is done so that when calculating the inverses
6+ # # of a large vector or set of matrices, we only have
7+ # # to perform each calculation once, and save
8+ # # it for later.
9+
10+
11+ # #DESCRIPTION OF makeCacheMatrix:
12+
13+ # # This function stores the method's inputted
14+ # # matrix in the cache for use later. It returns
15+ # # a list of the available getter and setter
16+ # # functions for the input matrix and its
17+ # # inverse (from the cache).
318
4- # # Write a short comment describing this function
519
6- makeCacheMatrix <- function (x = matrix ()) {
720
21+ # # Var i is the variable where the matrix will be
22+ # # stored (ie: the cache).
23+ # # setMat stores the input matrix
24+ # # getMat retrieves the input matrix
25+ # # setInv sets the inverse matrix into the cache.
26+ # # getInv returns the inverse matrix
27+
28+ # # This is copied from Roger Peng's supplied code
29+ # # for the assignment. I have explained the lines
30+ # # that I think are difficult to read.
31+
32+ makeCacheMatrix <- function (x = matrix ()) {
33+ i <- NULL # makes sure cache is clear
34+
35+ setMat <- function (y ) {
36+ x <<- y # #inputs the matrix.
37+ i <<- NULL # #So, again the cache is set to empty
38+ }
39+
40+ getMat <- function () x
41+ # #prints the input matrix
42+
43+ setInv <- function (inv ) i <<- inv
44+ # #stores the inverse matrix in the cache
45+ getInv <- function () i
46+ # #prints the inverse matrix
47+ list (setMat = setMat , getMat = getMat ,
48+ setInv = setInv ,
49+ getInv = getInv
50+ )
851}
952
53+ # #DESCRIPTION OF cacheSolve:
1054
11- # # Write a short comment describing this function
55+ # # This function solves for the inverse of
56+ # # an inputted matrix. It uses the function above
57+ # # to store and retrieve both the input matrix and
58+ # # the inverse matrix
1259
1360cacheSolve <- function (x , ... ) {
14- # # Return a matrix that is the inverse of 'x'
61+ # # Return a matrix that is the inverse of 'x'
62+
63+ invMat <- x $ getInv()
64+
65+ if (! is.null(i )) {
66+ message(" getting cached data"
67+ return (i )
68+ }
69+
70+ data <- x $ getMat()
71+ invMat <- solve(data )
72+ x $ setInv(invMat )
73+
74+ invMat
1575}
76+
77+ # # Thanks for reading! :)
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