## MB03BA

### Computing maps for Hessenberg index and signature array

[Specification] [Arguments] [Method] [References] [Comments] [Example]

Purpose

      To compute the suitable maps for Hessenberg index H and
      signature array S. Auxiliary routine for the periodic QZ
      algorithms.

Specification

          SUBROUTINE MB03BA( K, H, S, SMULT, AMAP, QMAP )
    C     .. Scalar Arguments ..
          INTEGER           K, H, SMULT
    C     .. Array Arguments ..
          INTEGER           AMAP(*), QMAP(*), S(*)

Arguments

Input/Output Parameters

      K       (input)  INTEGER
              The number of factors.  K >= 1.

      H       (input)  INTEGER
              Index which corresponds to A_1.

      S       (input)  INTEGER array, dimension (K)
              The signature array. Each entry of S must be 1 or -1.

      SMULT   (output)  INTEGER
              Signature multiplier. Entries of S are virtually
              multiplied by SMULT.

      AMAP    (output)  INTEGER array, dimension (K)
              The map for accessing the factors, that is,
              if AMAP(I) = J, then the factor A_I is stored at the J-th
              position in A.

      QMAP    (output)  INTEGER array, dimension (K)
              The map for accessing the orthognal transformation
              matrices, that is, if QMAP(I) = J, then the matrix Q_I is
              stored at the J-th position in Q.

Further Comments

      None

Example

Program Text

      None

Program Data

      None

Program Results

      None

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