From c5a55fde2958e0a15decb2b90ee04be6fc33c633 Mon Sep 17 00:00:00 2001
From: Gentle Yang <nodexy@gmail.com>
Date: Fri, 19 Dec 2014 18:19:47 +0800
Subject: [PATCH] finish two functions

---
 cachematrix.R | 28 +++++++++++++++++++++++-----
 1 file changed, 23 insertions(+), 5 deletions(-)

diff --git a/cachematrix.R b/cachematrix.R
index a50be65aa44..e7205f8d41c 100644
--- a/cachematrix.R
+++ b/cachematrix.R
@@ -1,15 +1,33 @@
-## Put comments here that give an overall description of what your
-## functions do
+## solve with cache 
 
-## Write a short comment describing this function
+## This function creates a special "matrix" object that can cache its inverse.
 
 makeCacheMatrix <- function(x = matrix()) {
-
+        ivs <- NULL
+        set <- function(y) {
+                x <<- y
+                ivs <<- NULL
+        }
+        get <- function() x
+        setinverse <- function(inverse) ivs <<- inverse
+        getinverse <- function() ivs
+        list(set = set, get = get,
+             setinverse = setinverse,
+             getinverse = getinverse)
 }
 
 
-## Write a short comment describing this function
+## cache martix inverse function
 
 cacheSolve <- function(x, ...) {
         ## Return a matrix that is the inverse of 'x'
+        ivs <- x$getinverse()
+        if(!is.null(ivs)) {
+                message("getting cached matrix inverse")
+                return(ivs)
+        }
+        data <- x$get()
+        ivs <- solve(data, ...)
+        x$setinverse(ivs)
+        ivs
 }