Update cachematrix.R

Author: quixoticblink

cachematrix.R

@@ -1,15 +1,55 @@
-## Put comments here that give an overall description of what your
-## functions do
+## Programming Assingment 2
+## Two functions 
+##  makeCacheMatrix - creates a list with functions
+##  cacheSolve - finds inverse of matrix checking previously cached matrix
 
-## Write a short comment describing this function
 
-makeCacheMatrix <- function(x = matrix()) {
+## creates a list with functions
+## set the value of matrix
+## get the value of matrix
+## set the value of inverse
+## get the value of inverse
 
+makeCacheMatrix <- function(x = matrix()) {
+  i<-NULL
+  set<-function(y){
+    x<<-y
+    i<<-NULL
+  }
+  get<-function() x
+  setmatrix<-function(solve) i<<- solve
+  getmatrix<-function() i
+  list(set=set, get=get, setmatrix=setmatrix,getmatrix=getmatrix)
 }
 
 
-## Write a short comment describing this function
+## Calculates mean of matrix
+## first checks to see if mean has already been calculated
+## if so skips computation
+## else calculates the mean
 
 cacheSolve <- function(x, ...) {
-        ## Return a matrix that is the inverse of 'x'
+  i<-x$getmatrix()
+  if(!is.null(i)){
+    message("getting cached data")
+    return(i)
+  }
+  matrix<-x$get()
+  i<-solve(matrix, ...)
+  x$setmatrix(i)
+  i
 }
+
+## --------------------------Test run commands----------------
+## > test<- rbind (c(1.0, -0.25), c(-0.25,1))
+## > z <- makeCacheMatrix(test)
+## > cacheSolve(z)
+## [,1]      [,2]
+## [1,] 1.0666667 0.2666667
+## [2,] 0.2666667 1.0666667
+## -----------if you again run then it says getting cached data-------
+## > cacheSolve(z)
+## getting cached data
+## [,1]      [,2]
+## [1,] 1.0666667 0.2666667
+## [2,] 0.2666667 1.0666667