cachematrix.R

## Put comments here that give an overall description of what your
## functions do

## Write a short comment describing this function

## This function creates a special "matrix" object that can cache its inverse.
makeCacheMatrix <- function(x = matrix()) {
    xInv <- NULL
    set <- function(y) {
        x <<- y
        xInv <<- NULL
    }
    get <- function() x
    setInvMatrix <- function(invMatrix) xInv <<- invMatrix
    getInvMatrix <- function() xInv
    list(set = set, get = get,
         setInvMatrix = setInvMatrix,
         getInvMatrix = getInvMatrix)
}


## 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 should retrieve the inverse from the cache.
cacheSolve <- function(x, ...) {
    ## Return a matrix that is the inverse of 'x'
    xInv <- x$getInvMatrix()
    if(!is.null(xInv)) {
        message("getting cached data")
        return(xInv)
    }
    data <- x$get()
    xInv <- solve(data, ...)
    x$setInvMatrix(xInv)
    xInv
}

# Test code
# m <- matrix(round(runif(9,1,10)),3,3)
# cm <- makeCacheMatrix(m)
# invCm <- cacheSolve(cm)
# invCm2 <- cacheSolve(cm)

# identical(invCm,invCm2)