Update cachematrix.R

Test criteria:
1) matrixObj <- makeCacheMatrix(matrix(1:4, 2, 2))
2) matrixObj$getInverse()  ## Returns NULL since matrix has not been solved yet
3) cacheSolve(matrixObj) ## Solves and returns matrix object
4) cacheSolve(matrixObj) rdpeng#3 Retruns matrix object from cache
5) matrixObj <- makeCacheMatrix(matrix(1:9, 3, 3))
6) cacheSolve(matrixObj) ## Returns message: Matrix is singular and cannot be inversed and stops

cachematrix.R

@@ -1,15 +1,59 @@
-## Put comments here that give an overall description of what your
-## functions do
-
-## Write a short comment describing this function
+## Caching the Inverse of a Matrix:
+## Matrix inversion is usually a costly computation and there may be some 
+## benefit to caching the inverse of a matrix rather than compute it repeatedly.
+## Below are a pair of functions that are used to create a special object that 
+## stores a matrix and caches its inverse.
 
+## This function creates a special "matrix" object that can cache its inverse
 makeCacheMatrix <- function(x = matrix()) {
-
+	m <- NULL
+	set <- function(y) {
+		x <<- y
+		m <<- NULL
+	}
+	get <- function() x
+	setInverse <- function(inverse) m <<- inverse
+	getInverse <- function() m
+	list(set = set,
+	     get = get,
+	     setInverse = setInverse,
+	     getInverse = getInverse)
+
+
 }
 
 
-## Write a short comment describing this function
-
+## This function returns a matrix that is the inverse of argument 'x'
+## Returns from cache if exists already otherwise calls makeCacheMatrix
 cacheSolve <- function(x, ...) {
-        ## Return a matrix that is the inverse of 'x'
+
+	m <- x$getInverse()
+	if(!is.null(m)) {
+		message("getting cached data")
+		return(m)
+	}
+
+	# Data was not found in the cache above...solve it
+
+	data <- x$get()
+
+	# Check if matrix can be inversed. Singular matrixes 
+	# cannot be inversed. No point in proceeding otherwise.
+
+	f <- function(j) class(try(solve(j),silent=T))=="matrix"
+
+	if(f(data)) {
+		m <- solve(data, ...)
+		x$setInverse(m)
+		m
+	}
+	else
+	{
+		# Provide a meaningful error and bail out
+		message("Matrix is singular and cannot be inversed")
+		stop("Retry with different data")
+	}
+
+
+
 }