## MA02EZ

### Store by (skew-)symmetry the upper or lower triangle of a (skew-)symmetric/Hermitian complex matrix, given the other triangle

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

Purpose

      To store by (skew-)symmetry the upper or lower triangle of a
      (skew-)symmetric/Hermitian complex matrix, given the other
      triangle. The option SKEW = 'G' allows to suitably deal with the
      diagonal of a general square triangular matrix.

Specification

          SUBROUTINE MA02EZ( UPLO, TRANS, SKEW, N, A, LDA )
    C     .. Scalar Arguments ..
          CHARACTER          SKEW, TRANS, UPLO
          INTEGER            LDA, N
    C     .. Array Arguments ..
          COMPLEX*16         A(LDA,*)

Arguments

Mode Parameters

      UPLO    CHARACTER*1
              Specifies which part of the matrix is given as follows:
              = 'U':  Upper triangular part;
              = 'L':  Lower triangular part.
              For all other values, the array A is not referenced.

      TRANS   CHARACTER*1
              Specifies whether to use transposition or conjugate
              transposition as follows:
              = 'T':  Use transposition;
              = 'C':  Use conjugate transposition.

      SKEW    CHARACTER*1
              Specifies whether the matrix is symmetric/Hermitian or
              skew-symmetric/Hermitian as follows:
              = 'G':  The matrix is not symmetric/Hermitian (general);
              = 'N':  The matrix is symmetric/Hermitian;
              = 'S':  The matrix is skew-symmetric/Hermitian.

Input/Output Parameters

      N       (input) INTEGER
              The order of the matrix A.  N >= 0.

      A       (input/output) COMPLEX*16 array, dimension (LDA,N)
              On entry, the leading N-by-N upper triangular part
              (if UPLO = 'U'), or lower triangular part (if UPLO = 'L'),
              of this array must contain the corresponding upper or
              lower triangle of the (skew-)symmetric/Hermitian matrix A.
              On exit, the leading N-by-N part of this array contains
              the (skew-)symmetric/Hermitian matrix A with all elements
              stored. If the resulted matrix should be Hermitian, the
              imaginary parts of the diagonal entries are set to zero.
              If the resulted matrix should be skew-Hermitian, the real
              parts of the diagonal entries are set to zero.

      LDA     INTEGER
              The leading dimension of the array A.  LDA >= max(1,N).

Further Comments

      None

Example

Program Text

      None

Program Data

      None

Program Results

      None

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