DORHR_COL01(3)
okay so bestie, this page is TESTING/LI...rhr_col01.f(3) from the Library Functions Manual β and we're about to get into some LAPACK test-subroutine business. π
π NAME π
TESTING/LIN/dorhr_col01.f
β¨ SYNOPSIS β¨
Functions/Subroutines
subroutine dorhr_col01 (m, n, mb1, nb1, nb2, result)
DORHR_COL01
π Function/Subroutine Documentation π
subroutine dorhr_col01 (integer m, integer n, integer mb1, integer nb1,
integer nb2, double precision, dimension(6) result)
DORHR_COL01
πΈ Purpose πΈ
DORHR_COL01 tests DORGTSQR and DORHR_COL using DLATSQR, DGEMQRT.
So yes: DLATSQR (part of DGEQR) and DGEMQRT (part of DGEMQR) have to be tested before this test. Order matters, bestie β this test is not doing the whole warm-up by itself. π«Ά
π§ Parameters π§
MβM is INTEGER; number of rows in test matrix.NβN is INTEGER; number of columns in test matrix.MB1βMB1 is INTEGER; number of row in row block in an input test matrix.NB1βNB1 is INTEGER; number of columns in column block an input test matrix.NB2βNB2 is INTEGER; number of columns in column block in an output test matrix.RESULTβRESULT is DOUBLE PRECISION array, dimension (6); results of each of the six tests below.
The whole RESULT vibe is this little cast of matrices and factors:
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 orthogonal 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 orthogonal 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 DGEMQRT,
Q * C, (Q**H) * C, D * Q, D * (Q**H) are
computed using DGEMM.
π Author π
- Univ. of Tennessee
- Univ. of California Berkeley
- Univ. of Colorado Denver
- NAG Ltd.
Definition at line 118 of file dorhr_col01.f.
π Author π
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