cachematrix.R

## This function returns a list of four functions to store a matrix 'x' and cache its inverse,
## so that the inverse matrix only needs to be calculated once.
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)
}


## This function returns a matrix that is the inverse of 'x'.  It uses makeCacheMatrix to cache
## the inverse function, and uses the cache if available.
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
}