cachematrix.R

# makeCacheMatrix creates 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 inverse of the matrix
# 4. get the value of inverse of the matrix

## Write a short comment describing this function

makeCacheMatrix <- function(x = matrix()) {
  inv <- NULL
  set <- function(y) {
    x <<- y
    inv <<- NULL
  }
  get <- function() x
  setinverse <- function(inverse) inv <<- inverse
  getinverse <- function() inv
  list(set=set, get=get, setinverse=setinverse, getinverse=getinverse)
}


## This function retunrs the inverse of the matrix 
# This function assumes that the matrix is always invertible.

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

#x = rbind(c(1, -1/4), c(-1/4, 1))
#m = makeCacheMatrix(x)
#m$get()
#[,1]  [,2]
#[1,]  1.00 -0.25
#[2,] -0.25  1.00
#> cacheSolve(m)
#[,1]      [,2]
#[1,] 1.0666667 0.2666667
#[2,] 0.2666667 1.0666667
#> cacheSolve(m)
#getting cached data.
#[,1]      [,2]
#[1,] 1.0666667 0.2666667
#[2,] 0.2666667 1.0666667
#