cachematrix.R

# makeCacheMatrix creates a special "vector", which is really a list containing 
# a function to :-
#
# 1) set the value of the matrix
# 2) get the value of the matrix
# 3) set the value of the inverse of a matrix
# 4) get the value of the inverse of a matrix
makeCacheMatrix <- function(x = matrix()) {
  i <- NULL
  set <- function(y) {
    x <<- y
    i <<- NULL
  }
  get <- function() x
  setInverse <- function(inverse) i <<- inverse
  getInverse <- function() i
  list(set = set, get = get, setInverse = setInverse, getInverse = getInverse)
}

#cacheSolve computes the inverse of the special "matrix" returned by makeCacheMatrix. 
#If the inverse has already been calculated (and the matrix has not changed), then 
#the cachesolve retrieves the inverse from the cache.
cacheSolve <- function(x, ...) {
  i <- x$getInverse()
  if(!is.null(i)) {
    message("getting cached data")
    return(i)
  }
  data <- x$get()
  i <- solve(data, ...)
  x$setInverse(i)
  i
}