subroutine pertobs 2,2
#if defined (DOC)
*
***s/r pertobs  - Perturb the observations for a Monte Carlo cycle
*
*
*Author  : M. Buehner *ARMA/MSC  Apr 2003
*Revision:
*
*    -------------------
**    Purpose: to initialize  * 
*
*
*Arguments
*    -NONE-
#endif
      IMPLICIT NONE
*implicits
#include "comlun.cdk"
#include "comrand.cdk"
c
      logical LEXIST
      integer II,IOS
      real*8 gasdev
c
      call printrev("SUBROUTINE pertobs :",20)
c
      WRITE(NULOUT,*) '------------------------------'
      WRITE(NULOUT,*) 'PERTURBING OBSERVATIONS IN CMA'
      WRITE(NULOUT,*) '------------------------------'
      inquire(file='./randnum.dat',exist=lexist)
      IF(LEXIST) THEN
        open(unit=39,form='unformatted',file='./randnum.dat')
        read(39) (RRAND(II),II=1,97)
        read(39) IX1,IX2,IX3,IFF
        close(39)
        write(NULOUT,*) 'READING IN RANDNUM'
      ENDIF
      CALL OBSSQRT
      CALL RANDOBS
      open(unit=39,form='unformatted',
     +	    file='./randnum.dat',STATUS='REPLACE',IOSTAT=IOS)
      write(39) (RRAND(II),II=1,97)
      write(39) IX1,IX2,IX3,IFF
      close(39)
      write(NULOUT,*) 'WRITING OUT RANDNUM'
c
      RETURN
      END