SLATEC Routines --- LSI ---

*DECK LSI
      SUBROUTINE LSI (W, MDW, MA, MG, N, PRGOPT, X, RNORM, MODE, WS, IP)
C***BEGIN PROLOGUE  LSI
C***SUBSIDIARY
C***PURPOSE  Subsidiary to LSEI
C***LIBRARY   SLATEC
C***TYPE      SINGLE PRECISION (LSI-S, DLSI-D)
C***AUTHOR  Hanson, R. J., (SNLA)
C***DESCRIPTION
C
C     This is a companion subprogram to LSEI.  The documentation for
C     LSEI has complete usage instructions.
C
C     Solve..
C              AX = B,  A  MA by N  (least squares equations)
C     subject to..
C
C              GX.GE.H, G  MG by N  (inequality constraints)
C
C     Input..
C
C      W(*,*) contains  (A B) in rows 1,...,MA+MG, cols 1,...,N+1.
C                       (G H)
C
C     MDW,MA,MG,N
C              contain (resp) var. dimension of W(*,*),
C              and matrix dimensions.
C
C     PRGOPT(*),
C              Program option vector.
C
C     OUTPUT..
C
C      X(*),RNORM
C
C              Solution vector(unless MODE=2), length of AX-B.
C
C      MODE
C              =0   Inequality constraints are compatible.
C              =2   Inequality constraints contradictory.
C
C      WS(*),
C              Working storage of dimension K+N+(MG+2)*(N+7),
C              where K=MAX(MA+MG,N).
C      IP(MG+2*N+1)
C              Integer working storage
C
C***ROUTINES CALLED  H12, HFTI, LPDP, R1MACH, SASUM, SAXPY, SCOPY, SDOT,
C                    SSCAL, SSWAP
C***REVISION HISTORY  (YYMMDD)
C   790701  DATE WRITTEN
C   890531  Changed all specific intrinsics to generic.  (WRB)
C   890618  Completely restructured and extensively revised (WRB & RWC)
C   891214  Prologue converted to Version 4.0 format.  (BAB)
C   900328  Added TYPE section.  (WRB)
C   920422  Changed CALL to HFTI to include variable MA.  (WRB)
C***END PROLOGUE  LSI