LinearRGradientReg <- function (theta, X, y, lambda){
  
  #   Compute gradient for regularized linear regression with multiple variables
  # 
  #   grad <- LinearRGradientReg(theta, X, y, lambda) computes the 
  #   gradient of using theta as the parameter for linear 
  #   regression to fit the data points in X and y. 
  
  # Initialize some useful values
  m <- length(y) # number of training examples
  
  # ====================== YOUR CODE HERE ========================
  # Instructions: Compute the gradient of regularized linear 
  #               regression for a particular choice of theta.
  #
  #               You should set grad to the gradient.
  #
  
  
  
  # ==============================================================
  
  return(grad)           
}