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CH(NM,N,AR,AI,W,MATZ,ZR,ZI,FV1,FV2,FM1,IERR)

       SUBROUTINE CH(NM,N,AR,AI,W,MATZ,ZR,ZI,FV1,FV2,FM1,IERR)
 C
       INTEGER I,J,N,NM,IERR,MATZ
       DOUBLE PRECISION AR(NM,N),AI(NM,N),W(N),ZR(NM,N),ZI(NM,N),
      X       FV1(N),FV2(N),FM1(2,N)
 C
 C     THIS SUBROUTINE CALLS THE RECOMMENDED SEQUENCE OF
 C     SUBROUTINES FROM THE EIGENSYSTEM SUBROUTINE PACKAGE (EISPACK)
 C     TO FIND THE EIGENVALUES AND EIGENVECTORS (IF DESIRED)
 C     OF A COMPLEX HERMITIAN MATRIX.
 C
 C     ON INPUT
 C
 C        NM  MUST BE SET TO THE ROW DIMENSION OF THE TWO-DIMENSIONAL
 C        ARRAY PARAMETERS AS DECLARED IN THE CALLING PROGRAM
 C        DIMENSION STATEMENT.
 C
 C        N  IS THE ORDER OF THE MATRIX  A=(AR,AI).
 C
 C        AR  AND  AI  CONTAIN THE REAL AND IMAGINARY PARTS,
 C        RESPECTIVELY, OF THE COMPLEX HERMITIAN MATRIX.
 C
 C        MATZ  IS AN INTEGER VARIABLE SET EQUAL TO ZERO IF
 C        ONLY EIGENVALUES ARE DESIRED.  OTHERWISE IT IS SET TO
 C        ANY NON-ZERO INTEGER FOR BOTH EIGENVALUES AND EIGENVECTORS.
 C
 C     ON OUTPUT
 C
 C        W  CONTAINS THE EIGENVALUES IN ASCENDING ORDER.
 C
 C        ZR  AND  ZI  CONTAIN THE REAL AND IMAGINARY PARTS,
 C        RESPECTIVELY, OF THE EIGENVECTORS IF MATZ IS NOT ZERO.
 C
 C        IERR  IS AN INTEGER OUTPUT VARIABLE SET EQUAL TO AN ERROR
 C           COMPLETION CODE DESCRIBED IN THE DOCUMENTATION FOR TQLRAT
 C           AND TQL2.  THE NORMAL COMPLETION CODE IS ZERO.
 C
 C        FV1, FV2, AND  FM1  ARE TEMPORARY STORAGE ARRAYS.
 C
 C     QUESTIONS AND COMMENTS SHOULD BE DIRECTED TO BURTON S. GARBOW,
 C     MATHEMATICS AND COMPUTER SCIENCE DIV, ARGONNE NATIONAL LABORATORY
 C
 C     THIS VERSION DATED AUGUST 1983.
 C
 C     ------------------------------------------------------------------
 C