 Usage:  {freq,calibr,discr}=VaRgrdiag(int,sig,real,g)  
 
 Input:

  int                    mx2 matrix containing intervals in the rows. 
                         
  sig                    nx1 vector of predicted standard deviations 
                         (assume normality) 
                         
  real                   nx1 vector of realizations. 
                         
  g                      scalar, number of grid points. 
                         
 Output:

  freq                   graphical object containing rel. frequencies 
                         of the probability forecasts calculated on the 
                         given number of grid points. 
                         
  calibr                 graphical object containing the calibration plot. 
                         
  discr                  graphical object containing the discrimination plot. 
                         
--------------------------------------------------------------
(C) MD*TECH Method and Data Technologies, 17.8.2000
