Checking in function for cachable matrix

Author: Brian Donaldson

cachematrix.R

@@ -1,15 +1,55 @@
 ## Put comments here that give an overall description of what your
 ## functions do
 
+2 functions.  The first function creates a special matrix object that supports caching its inverse.  The second function produces the inverse to the matrix object, using the object's cache if set, and otherwise computing the result.
+
 ## Write a short comment describing this function
+Function returns a matrix object that supports caching its inverse.
 
 makeCacheMatrix <- function(x = matrix()) {
-
+  m <- NULL
+  set <- function(y) {
+    x <<- y
+    m <<- NULL
+  }
+  get <- function() x
+  setsolution <- function(solution) m <<- solution
+  getsolution <- function() m
+  list(set = set, get = get,
+       setsolution = setsolution,
+       getsolution = getsolution)
 }
 
-
 ## Write a short comment describing this function
+Function retrieves the inverse of matrix X, using the cache, and otherwise performs the solve method and then caches the result.
 
+## Return a matrix that is the inverse of 'x'
 cacheSolve <- function(x, ...) {
-        ## Return a matrix that is the inverse of 'x'
+  m <- x$getsolution()
+  if(!is.null(m)) {
+    message("getting cached data")
+    return(m)
+  }
+  data <- x$get()
+  m <- solve(data, ...)
+  x$setsolution(m)
+  m
 }
+
+## Test
+tryme <- makeCacheMatrix(matrix(c(1,2,3,4), nrow=2, ncol=2))
+cacheSolve(tryme)
+cacheSolve(tryme)
+
+## Test
+# > tryme <- makeCacheMatrix(matrix(c(1,2,3,4), nrow=2, ncol=2))
+# > cacheSolve(tryme)
+# [,1] [,2]
+# [1,]   -2  1.5
+# [2,]    1 -0.5
+# > cacheSolve(tryme)
+# getting cached data
+# [,1] [,2]
+# [1,]   -2  1.5
+# [2,]    1 -0.5
+#