# chpsl.f

          SUBROUTINE CHPSL (AP, N, KPVT, B)
    C***BEGIN PROLOGUE  CHPSL
    C***PURPOSE  Solve a complex Hermitian system using factors obtained
    C            from CHPFA.
    C***LIBRARY   SLATEC (LINPACK)
    C***CATEGORY  D2D1A
    C***TYPE      COMPLEX (SSPSL-S, DSPSL-D, CHPSL-C, CSPSL-C)
    C***KEYWORDS  HERMITIAN, LINEAR ALGEBRA, LINPACK, MATRIX, PACKED, SOLVE
    C***AUTHOR  Bunch, J., (UCSD)
    C***DESCRIPTION
    C
    C     CHISL solves the complex Hermitian system
    C     A * X = B
    C     using the factors computed by CHPFA.
    C
    C     On Entry
    C
    C        AP      COMPLEX(N*(N+1)/2)
    C                the output from CHPFA.
    C
    C        N       INTEGER
    C                the order of the matrix  A .
    C
    C        KVPT    INTEGER(N)
    C                the pivot vector from CHPFA.
    C
    C        B       COMPLEX(N)
    C                the right hand side vector.
    C
    C     On Return
    C
    C        B       the solution vector  X .
    C
    C     Error Condition
    C
    C        A division by zero may occur if  CHPCO  has set RCOND .EQ. 0.0
    C        or  CHPFA  has set INFO .NE. 0  .
    C
    C     To compute  INVERSE(A) * C  where  C  is a matrix
    C     with  P  columns
    C           CALL CHPFA(AP,N,KVPT,INFO)
    C           IF (INFO .NE. 0) GO TO ...
    C           DO 10 J = 1, P
    C              CALL CHPSL(AP,N,KVPT,C(1,J))
    C        10 CONTINUE
    C
    C***REFERENCES  J. J. Dongarra, J. R. Bunch, C. B. Moler, and G. W.
    C                 Stewart, LINPACK Users' Guide, SIAM, 1979.
    C***ROUTINES CALLED  CAXPY, CDOTC
    C***REVISION HISTORY  (YYMMDD)
    C   780814  DATE WRITTEN
    C   890531  Changed all specific intrinsics to generic.  (WRB)
    C   890831  Modified array declarations.  (WRB)
    C   891107  Modified routine equivalence list.  (WRB)
    C   891107  REVISION DATE from Version 3.2
    C   891214  Prologue converted to Version 4.0 format.  (BAB)
    C   900326  Removed duplicate information from DESCRIPTION section.
    C           (WRB)
    C   920501  Reformatted the REFERENCES section.  (WRB)
    C***END PROLOGUE  CHPSL