      SUBROUTINE MWCONST

C     CONSTANT MOLECULAR WEIGHT MODEL

      implicit DOUBLE PRECISION (a-h,o-z)



      PARAMETER (NWARSZ=1000)

      COMMON/WW/ dum(10),MAXW,W(NWARSZ)

      DOUBLE PRECISION MMODEL,MFORM,MID

C

C     MOLECULAR   250-274

      EQUIVALENCE (W(250),MMODEL),(W(251),MFORM),(W(252),MID)

C

C     COMMON DECK "MM" INSERTED HERE

      DOUBLE PRECISION M,MODM

      COMMON/MM/MODM(4),M,PMT,PMR,PMTH,PMPH

      DOUBLE PRECISION  MLCNST

      EQUIVALENCE (W(253),MLCNST)

C     COMMON DECK "B7" INSERTED HERE

      INTEGER MMX,MNTBL,MITBL,MFRMTBL,IDSM(10)

      DOUBLE PRECISION MGP

      COMMON/B7/MMX,MNTBL(10),MITBL(10),MFRMTBL(10),MGP(10)

      EQUIVALENCE (MGP,IDSM)

      DATA MMX/1/

      DATA MNTBL/1,11,8*0/

      DATA MITBL/1,9*0/

      DATA MFRMTBL/1,9*0/

C

      ENTRY IMOLWT

C

      if (w(250) .ne. 1) then

           PRINT*,' Model check number mismatch: '

           STOP ' W(250) should be 1 if you are using model MCONST.'

      endif

C

      MODM(1)=6HMCONST

      MODM(2)= w(252)

C

      RETURN

C

      ENTRY MOLWT

      M=MLCNST

      CALL CLEAR(PMT,4)

      END

