ProgrammingAssignment2

makeCacheMatrix <- function( x=matrix()){
matrix_inv <NULL

    set <- function(y){
            x <<- y
            matrix_inv <<- NULL
    }
    get <- function() x
    setinverse <- function( inverse) matrix_inv <<- inverse
    getinverse <- function() matrix_inv



    list(set = set, get = set, 
         setinverse = setinverse, getinverse = getinverse)

}

cacheSolve <- function(x, ...){
matrix_inv <- x$getinverse()
if(!is.null(matrix_inv)){
message("getting cached data")
return(matrix_inv)
}

    my_matrix <- x$get()
    matrix_inv <- solve(my_matrix, ...)
    x$setinverse(matrix_inv)

    inv

}

[thinkxidr]

it's clear