functions for caching inverse implemtned

Author: lstanczak

cachematrix.R

@@ -1,15 +1,35 @@
-## Put comments here that give an overall description of what your
-## functions do
-
-## Write a short comment describing this function
-
-makeCacheMatrix <- function(x = matrix()) {
-
-}
-
-
-## Write a short comment describing this function
-
-cacheSolve <- function(x, ...) {
-        ## Return a matrix that is the inverse of 'x'
-}
+## Following functions serve as a cache for matrix inverse.
+
+
+## This function returns list of methods for accessing target matrix and
+## inverse result using closure mechanism
+
+makeCacheMatrix <- function(x = matrix()) {
+  inverse <- NULL
+  set <- function(y) {
+    x <<- y
+    inverse <<- NULL
+  }
+  get <- function() x
+  setinverse <- function(i) inverse <<- i
+  getinverse <- function() inverse
+  list(set = set, get = get,
+       setinverse = setinverse,
+       getinverse = getinverse)
+}
+
+
+## Function computes inverse of matrix if it wasn't computed before, 
+## or returns cached result. X argument should be a list created by
+## makeCacheMatrix function
+
+cacheSolve <- function(x, ...) {
+  i <- x$getinverse()
+  if(!is.null(i)) {
+    return(i)
+  }
+  data <- x$get()
+  i <- solve(data, ...)
+  x$setinverse(i)
+  i
+}