Update cachematrix.R

cachematrix.R

@@ -7,17 +7,28 @@ https://www.coursera.org/learn/r-programming/discussions/weeks/3/threads/ePlO1eM
 
 R session:
 
-> # Matrices for testing the R functions 
-> # makeCacheMatrix and cacheSolve
-> # in the Coursera R Programming Course
-> #
-> # First, 
-> # If you haven't read Leonard Greski's invaluable
-> # [TIPS] Demystifying makeVector()  Post
-> # be sure to do so.
-> #
-> # A simple matrix m1 with a simple matrix inverse n1
-> # Define
+>makeCacheMatrix <- function(x = matrix()) {
+  inv <- NULL
+
+  # Set the matrix
+  set <- function(y) {
+    x <<- y
+    inv <<- NULL
+  }
+
+  # Get the matrix
+  get <- function() x
+
+  # Set the inverse
+  setInverse <- function(inverse) inv <<- inverse
+
+  # Get the inverse
+  getInverse <- function() inv
+
+  # Return a list of methods
+  list(set = set, get = get, setInverse = setInverse, getInverse = getInverse)
+}
+
 > m1 <- matrix(c(1/2, -1/4, -1, 3/4), nrow = 2, ncol = 2)
 > m1
       [,1]  [,2]
@@ -85,8 +96,25 @@ R session:
 > #
 > myMatrix_object <- makeCacheMatrix(m1)
 > 
-> # and then
-> # cacheSolve(myMatrix_object)
+> cacheSolve <- function(x, ...) {
+  # Check if the inverse is already calculated
+  inv <- x$getInverse()
+
+  if (!is.null(inv)) {
+    message("getting cached data")
+    return(inv)
+  }
+
+  # Calculate the inverse
+  mat <- x$get()
+  inv <- solve(mat, ...)
+
+  # Store the inverse in the cache
+  x$setInverse(inv)
+
+  inv
+}
+
 > 
 > # should return exactly the matrix n1
 > cacheSolve(myMatrix_object)
@@ -117,4 +145,4 @@ getting cached data
      [,1] [,2]
 [1,]    3    7
 [2,]    1    5
-> 
+>