zunhr_col02.f - Man Page

subroutine zunhr_col02 (m, n, mb1, nb1, nb2, result)
ZUNHR_COL02

ZUNHR_COL02

Purpose:

 ZUNHR_COL02 tests ZUNGTSQR_ROW and ZUNHR_COL inside ZGETSQRHRT
 (which calls ZLATSQR, ZUNGTSQR_ROW and ZUNHR_COL) using ZGEMQRT.
 Therefore, ZLATSQR (part of ZGEQR), ZGEMQRT (part of ZGEMQR)
 have to be tested before this test.

Parameters

M

          M is INTEGER
          Number of rows in test matrix.

N

          N is INTEGER
          Number of columns in test matrix.

MB1

          MB1 is INTEGER
          Number of row in row block in an input test matrix.

NB1

          NB1 is INTEGER
          Number of columns in column block an input test matrix.

NB2

          NB2 is INTEGER
          Number of columns in column block in an output test matrix.

RESULT

          RESULT is DOUBLE PRECISION array, dimension (6)
          Results of each of the six tests below.

            A is a m-by-n test input matrix to be factored.
            so that A = Q_gr * ( R )
                               ( 0 ),

            Q_qr is an implicit m-by-m unitary Q matrix, the result
            of factorization in blocked WY-representation,
            stored in ZGEQRT output format.

            R is a n-by-n upper-triangular matrix,

            0 is a (m-n)-by-n zero matrix,

            Q is an explicit m-by-m unitary matrix Q = Q_gr * I

            C is an m-by-n random matrix,

            D is an n-by-m random matrix.

          The six tests are:

          RESULT(1) = |R - (Q**H) * A| / ( eps * m * |A| )
            is equivalent to test for | A - Q * R | / (eps * m * |A|),

          RESULT(2) = |I - (Q**H) * Q| / ( eps * m ),

          RESULT(3) = | Q_qr * C - Q * C | / (eps * m * |C|),

          RESULT(4) = | (Q_gr**H) * C - (Q**H) * C | / (eps * m * |C|)

          RESULT(5) = | D * Q_qr - D * Q | / (eps * m * |D|)

          RESULT(6) = | D * (Q_qr**H) - D * (Q**H) | / (eps * m * |D|),

          where:
            Q_qr * C, (Q_gr**H) * C, D * Q_qr, D * (Q_qr**H) are
            computed using ZGEMQRT,

            Q * C, (Q**H) * C, D * Q, D * (Q**H)  are
            computed using ZGEMM.

Author

Univ. of Tennessee

Univ. of California Berkeley

Univ. of Colorado Denver

NAG Ltd.

Definition at line 119 of file zunhr_col02.f.