function lnblk(string,nchar)
c
c=======================================================================
c                                                                    ===
c  This function returns the character position of the last non-     ===
c  blank character in STRING.  The value NCHAR tells LNBLK where     ===
c  to start the search for the last non-blank character.             ===
c                                                                    ===
c=======================================================================
c
c-----------------------------------------------------------------------
c  Define local data.
c-----------------------------------------------------------------------
c
      integer i,ic,istart,nchar
      integer lnblk
      character*(*) string
c
c-----------------------------------------------------------------------
c  Begin executable code.
c-----------------------------------------------------------------------
c
c  Strip leading blank characters.
c
      ic=0
      do 10 i=1,nchar
        if(string(i:i).eq.' ') then
          ic=ic+1
        else
          goto 20
        endif
  10  continue
  20  istart=ic+1
      if(istart.lt.nchar) string=string(istart:nchar)
c
c  Strip trailing blank character and determine the its length.
c
      do 30 i=nchar,1,-1
        if(string(i:i).ne.' ') goto 40
  30  continue
      lnblk=0
      return
  40  lnblk=i
      return
      end