diff --git a/cachematrix.R b/cachematrix.R index a50be65aa44..468c602290f 100644 --- a/cachematrix.R +++ b/cachematrix.R @@ -1,15 +1,43 @@ -## Put comments here that give an overall description of what your -## functions do +## These functions provide a way to cache the result of a possibly slow calculation, +## such as the inverse of a matrix. +## The matrix to be inverted must be inputted into the makeCacheMatrix. +## Then the object returned by makeCacheMatrix must be passed to the cacheSolve +## function which will return the inverted matrix (either cached or computed) -## Write a short comment describing this function +## This function creates a special "matrix" object that can cache its inverse. +## Actually it's only a list of function to operate with the matrix value and +## store its inverse makeCacheMatrix <- function(x = matrix()) { - + + inverse <- NULL + set <- function(m) { + x <<- m + inverse <<- NULL + } + get <- function() x + setinverse <- function(inv) inverse <<- inv + getinverse <- function() inverse + list(set = set, get = get, + setinverse = setinverse, + getinverse = getinverse) } -## Write a short comment describing this function +## This function computes the inverse of the special "matrix" returned by +## makeCacheMatrix above. +## If the inverse has already been calculated (and the matrix has not changed), +## then the cachesolve retrieves the inverse from the cache printing a log message. cacheSolve <- function(x, ...) { - ## Return a matrix that is the inverse of 'x' + + inverse <- x$getinverse() + if(!is.null(inverse)) { + message("getting cached data") + return(inverse) + } + data <- x$get() + inverse <- solve(data, ...) + x$setinverse(inverse) + inverse }