cachematrix.R

## Here we have two functions:
## The first one cache the inverse of a matrix
## The second one computes de inverse of a matrix

## This function receive a matrix as a parameter, create an object 
## that stores the inverse of the given matrix

makeCacheMatrix <- function(x = matrix()) {
  m <- NULL
  set <- function(y) {
    x <<- y
    m <<- NULL
  }

  get <- function() x
  setinv <- function(solve) m <<- solve
  getinv <- function() m
  list(set = set, get = get,
       setinv = setinv,
       getinv = getinv)
}


## ## The following is a pair of functions that cache and compute the 
## inverse of a matrix.

## This function creates a special "matrix" object
## that can cache its inverse.

makeCacheMatrix <- function(mtx = matrix()) {
  inverse <- NULL
  set <- function(x) {
    mtx <<- x;
    inverse <<- NULL;
  }
  get <- function() return(mtx);
  setinv <- function(inv) inverse <<- inv;
  getinv <- function() return(inverse);
  return(list(set = set, get = get, setinv = setinv, getinv = getinv))
}

## This function calculates the inverse of the matrix returned by the previous function
## If the inverse has already been calculated, then the following function should just 
## retrieve the inverse from the "store" variable.

cacheSolve <- function(mtx, ...) {
  inverse <- mtx$getinv()
  if(!is.null(inverse)) {
    message("Getting cached data...")
    return(inverse)
  }
  data <- mtx$get()
  invserse <- solve(data, ...)
  mtx$setinv(inverse)
  return(inverse)
}

cacheSolve <- function(x, ...) {
  m <- x$getinv()
  if(!is.null(m)) {
    message("getting cached data")
    return(m)
  }
  data <- x$get()
  m <- solve(data, ...)
  x$setinv(m)
  m
        ## Return a matrix that is the inverse of 'x'
}