Update cachematrix.R

cachematrix.R

@@ -2,14 +2,45 @@
 ## functions do
 
 ## Write a short comment describing this function
-
+## Create a special matrix object that can cache its inverse
+## Returns four functions: set, get, setinv, getinv
 makeCacheMatrix <- function(x = matrix()) {
-
+        # Stores the cached inverse
+        inv<- NULL
+        # Assigns and clears cached inverse
+        set<- function(y) {
+                x <<- y
+                inv <<- NULL
+        }
+        # Returns current matrix
+        get<-function() x
+        # Stores inversed matrix in cache
+        setinv<-function(inverse) inv<<- inverse
+        # Retrieves cached inverse
+        getinv<-function() inv
+        # Return list of the four functions created
+        list(set = set, get = get,
+             setinv=setinv,
+             getinv=getinv)
 }
 
 
 ## Write a short comment describing this function
-
+## Compute the inverse of the matrix created by makeCacheMatrix
+## If already cached, return the cached value
 cacheSolve <- function(x, ...) {
         ## Return a matrix that is the inverse of 'x'
+
+        # Gets cached inverse
+        inv<-x$getinv()
+        # IF cached inverse exists, return it
+        if (!is.null(inv)) {
+                return(inv)
+        }
+        # Else compute the inverse
+        mat<-x$get()
+        inv<-solve(mat, ...)
+        x$setinv(inv)
+
+        inv
 }