LOGICAL FUNCTION OPINV(ID1, ID2, W, IW)
USE Numeric_Kinds_Module
!
!   $RCSfile: opinv.f,v $ $Revision: 1.3 $
!   $Date: 89/07/28 09:57:27 $
!   $State: Stable $
!
!
! **********************************************************************
!
!     PURPOSE -
!
!         DRIVER ROUTINE FOR THE SOLVER ROUTINE. SOLVES
!         (LDL(T))*VEC(ID)=VEC(ID2).
!
!     INPUT PARAMETERS -
!
!         ID1    = IDENTIFIER OF THE RESULTING VECTOR.
!         ID2    = IDENTIFIER OF THE INCOMING VECTOR.
!
!     PLEASE SEE THE PROGRAMMERS GUIDE FOR INFORMATION ABOUT
!     PARAMETERS NOT EXPLAINED ABOVE, AND FOR MORE DETAILS ABOUT
!     THE FUNCTION OF THE ROUTINE.
!
!
! **********************************************************************
!
REAL(Kind=WP_Kind)   SECOND, SMALL, ST, TIME, W(1)
INTEGER   AD1, AD2, ADDRSS, COUNT, D, DAFILE, DUMMY, FREE, ID1,  ID2, IW(1), K, KFILE, LEN, LP, M, MAXL, N, NBADMU,  &
                NMXRST, NOACTN, NOR, NREAD, NWRITE, READID, READK, SAEVAL, SAVE, SAVFRE, VER, WRITID
LOGICAL   ALLOC, DIAGM, F, MEQI, T
COMMON   /STLMAC/ NOACTN, FREE, SAVE, SAVFRE
COMMON   /STLMAD/ ADDRSS, DAFILE, KFILE, LP, MAXL, NREAD, NWRITE
COMMON   /STLMDS/ K, M, D, DIAGM
COMMON   /STLMIO/ SAEVAL, READID, WRITID, READK, N
COMMON   /STLMMI/ MEQI
COMMON   /STLMST/ TIME(24), COUNT(24), NBADMU, NMXRST, DUMMY
COMMON   /STLMTF/ T, F
COMMON   /STLMVR/ SMALL, VER
!
DATA      NOR  / 13 /
!
ST = SECOND(DUMMY)
COUNT(NOR) = COUNT(NOR) + 1
OPINV = T
!
IF(VER == 3) GOTO 10
IF(.NOT. ALLOC(ID1, ID2, AD1, AD2, NOACTN, W, IW(ADDRSS))) GOTO 8888
!
IF(VER == 2) GOTO 20
CALL SOLVE(W(AD1), W(AD2), W(K), IW(D), N)
GOTO 9999
!
10    CALL SOL3(ID1, ID2, W, IW, N, LEN)
20    IF(VER == 2) CALL SOL2(W(AD1), W(AD2),  W, IW, N, LEN)
IF(.NOT. LEN > 0) GOTO 9999
  CALL ERROR(102, LEN)
  CALL ERROR(102, 102)
!
8888  OPINV = F
CALL ERROR(NOR, NOR)
!
9999  TIME(NOR) = TIME(NOR) + SECOND(DUMMY) - ST
RETURN
END