Program to cache the inverse of a matrix

Mballo · Mballo · commit 15523364af93 · 2014-04-17T17:01:27.000Z
diff --git a/cachematrix.R b/cachematrix.R
@@ -1,24 +1,41 @@
+#This program keep in memory the result of an inverse of a matrix
+
+#The function makeCacheMatrix create a special matrix and has 4 sub functions
 makeCacheMatrix <- function(x = matrix()) {
-  m <- NULL
-  set <- function(y) {
-    x <<- y
-    m <<- NULL
-  }
-  get <- function() x
-  setsolve <- function(solve) m <<- solve
-  getsolve <- function() m
-  list(set = set, get = get,
-       setsolve = setsolve,
-       getsolve = getsolve)
+        m <- NULL
+        
+        #sub function 1 set: to set the value of the matrix
+        set <- function(y) {
+                x <<- y
+                m <<- NULL
+        }
+        
+        #sub function 2 get: to get the value of the matrix
+        get <- function() x
+        
+        #sub function 3 setsolve: to set the value of the inverse of the matrix
+        setsolve <- function(solve) 
+                m <<- solve
+        
+        #sub function 4 getsolve: to get the value of the inverse of the matrix
+        getsolve <- function() m
+        list(set = set, get = get,
+             setsolve = setsolve,
+             getsolve = getsolve)
 }
+
+#The function cacheSolve calculates the inverse of a matrix created with the makeCacheMatrix
 cacheSolve <- function(x, ...) {
-  m <- x$getsolve()
-  if(!is.null(m)) {
-    message("getting cached data")
-    return(m)
-  }
-  data <- x$get()
-  m <- solve(data, ...)
-  x$setsolve(m)
-  m
-}
+        #If the inverse was calculated before, return the value  
+        m <- x$getsolve()
+        if(!is.null(m)) {
+                message("getting cached data")
+                return(m)
+        }
+        #Else calculate the inverse of the matrix and add it to the list
+        data <- x$get()
+        m <- solve(data, ...)
+        x$setsolve(m)
+        m
+}
+
