SLATEC Routines --- BVPOR ---

*DECK BVPOR
      SUBROUTINE BVPOR (Y, NROWY, NCOMP, XPTS, NXPTS, A, NROWA, ALPHA,
     +   NIC, B, NROWB, BETA, NFC, IFLAG, Z, MXNON, P, NTP, IP, W, NIV,
     +   YHP, U, V, COEF, S, STOWA, G, WORK, IWORK, NFCC)
C***BEGIN PROLOGUE  BVPOR
C***SUBSIDIARY
C***PURPOSE  Subsidiary to BVSUP
C***LIBRARY   SLATEC
C***TYPE      SINGLE PRECISION (BVPOR-S, DBVPOR-D)
C***AUTHOR  Watts, H. A., (SNLA)
C***DESCRIPTION
C
C **********************************************************************
C     INPUT to BVPOR    (items not defined in BVSUP comments)
C **********************************************************************
C
C     NOPG = 0 -- Orthonormalization points not pre-assigned
C          = 1 -- Orthonormalization points pre-assigned
C
C     MXNON = Maximum number of orthogonalizations allowed.
C
C     NDISK = 0 -- IN-CORE storage
C           = 1 -- DISK storage.  Value of NTAPE in data statement
C                  is set to 13.  If another value is desired,
C                  the data statement must be changed.
C
C     INTEG = Type of integrator and associated test to be used
C             to determine when to orthonormalize.
C
C             1 -- Use GRAM-SCHMIDT test and DERKF
C             2 -- Use GRAM-SCHMIDT test and DEABM
C
C     TOL = Tolerance for allowable error in orthogonalization test.
C
C     NPS = 0 Normalize particular solution to unit length at each
C             point of orthonormalization.
C         = 1 Do not normalize particular solution.
C
C     NTP = Must be .GE. NFC*(NFC+1)/2.
C
C
C     NFCC = 2*NFC for special treatment of a complex valued problem
C
C     ICOCO = 0 Skip final computations (superposition coefficients
C               and ,hence, boundary problem solution)
C           = 1 Calculate superposition coefficients and obtain
C               solution to the boundary value problem
C
C **********************************************************************
C     OUTPUT from BVPOR
C **********************************************************************
C
C     Y(NROWY,NXPTS) = Solution at specified output points.
C
C     MXNON = Number of orthonormalizations performed by BVPOR.
C
C     Z(MXNON+1) = Locations of orthonormalizations performed by BVPOR.
C
C     NIV = Number of independent vectors returned from MGSBV. Normally
C        this parameter will be meaningful only when MGSBV returns with
C           MFLAG = 2.
C
C **********************************************************************
C
C     The following variables are in the argument list because of
C     variable dimensioning. In general, they contain no information of
C     use to the user.  The amount of storage set aside by the user must
C     be greater than or equal to that indicated by the dimension
C     statements.   For the DISK storage mode, NON = 0 and KPTS = 1,
C     while for the IN-CORE storage mode, NON = MXNON and KPTS = NXPTS.
C
C     P(NTP,NON+1)
C     IP(NFCC,NON+1)
C     YHP(NCOMP,NFC+1)  plus an additional column of the length  NEQIVP
C     U(NCOMP,NFC,KPTS)
C     V(NCOMP,KPTS)
C     W(NFCC,NON+1)
C     COEF(NFCC)
C     S(NFC+1)
C     STOWA(NCOMP*(NFC+1)+NEQIVP+1)
C     G(NCOMP)
C     WORK(KKKWS)
C     IWORK(LLLIWS)
C
C **********************************************************************
C     Subroutines used by BVPOR
C         LSSUDS -- Solves an underdetermined system of linear
C                   equations.  This routine is used to get a full
C                   set of initial conditions for integration.
C                   Called by BVPOR
C
C         SVECS -- Obtains starting vectors for special treatment
C                  of complex valued problems , called by BVPOR
C
C         RKFAB -- Routine which conducts integration using DERKF or
C                   DEABM
C
C         STWAY -- Storage for backup capability, called by
C                   BVPOR and REORT
C
C         STOR1 -- Storage at output points, called by BVPOR,
C                  RKFAB, REORT and STWAY.
C
C         SDOT -- Single precision vector inner product routine,
C                   called by BVPOR, SCOEF, LSSUDS, MGSBV,
C                   BKSOL, REORT and PRVEC.
C         ** NOTE **
C         A considerable improvement in speed can be achieved if a
C         machine language version is used for SDOT.
C
C         SCOEF -- Computes the superposition constants from the
C                  boundary conditions at Xfinal.
C
C         BKSOL -- Solves an upper triangular set of linear equations.
C
C **********************************************************************
C
C***SEE ALSO  BVSUP
C***ROUTINES CALLED  BKSOL, LSSUDS, RKFAB, SCOEF, SDOT, STOR1, STWAY,
C                    SVECS
C***COMMON BLOCKS    ML15TO, ML18JR, ML8SZ
C***REVISION HISTORY  (YYMMDD)
C   750601  DATE WRITTEN
C   890531  Changed all specific intrinsics to generic.  (WRB)
C   890831  Modified array declarations.  (WRB)
C   890921  Realigned order of variables in certain COMMON blocks.
C           (WRB)
C   891214  Prologue converted to Version 4.0 format.  (BAB)
C   900328  Added TYPE section.  (WRB)
C   910722  Updated AUTHOR section.  (ALS)
C***END PROLOGUE  BVPOR