add additional comments and include helper test script whose contents I used on console to verify

sabrams · sabrams · commit 8d3d468b791d · 2016-02-21T21:50:02.000-05:00
diff --git a/cachematrix.R b/cachematrix.R
@@ -22,6 +22,9 @@ makeCacheMatrix <- function(x = matrix()) {
 
 ## Returns inverse of x, storing the computation of the inverse
 ## x is not actually a matrix, but rather a list generated by makeCacheMatrix
+## This will set the 'internal' inverse matrix for mackCacheMatrix context if
+## it doesn't already exist, and will simply return that matrix if it exists w/o
+## recomputing.
 cacheSolve <- function(x, ...) {
   
   m <- x$getinv()
diff --git a/test.R b/test.R
@@ -0,0 +1,10 @@
+source('./cachematrix.R')
+x <- matrix(1:20,  nrow=3, ncol=2)
+y <- matrix(100:106,  nrow=3, ncol=2)
+z <- matrix(c("a", "v", "b", "aa", "ab", "cc"),  nrow=3, ncol=3)
+cmx <- makeCacheMatrix(x)
+cmy <- makeCacheMatrix(y)
+cmz <- makeCacheMatrix(z)
+invx <- cacheSolve(cmx)
+invy <- cacheSolve(cmy)
+invz <- cacheSolve(cmz)
