SRC/cunbdb6.f(3)

💅 NAME 💅

Straight from the Library Functions Manual, bestie: this page is for SRC/cunbdb6.f. That's the file, that's the name, and we're already slaying.

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✨ SYNOPSIS ✨

Functions/Subroutines

• subroutine cunbdb6 (m1, m2, n, x1, incx1, x2, incx2, q1, ldq1, q2, ldq2, work, lwork, info) — the one and only CUNBDB6, no cap 💅

subroutine cunbdb6 (m1, m2, n, x1, incx1, x2, incx2, q1, ldq1, q2, ldq2,
    work, lwork, info)

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🦋 Function/Subroutine Documentation 🦋

Okay so here's the full signature, bestie — she's giving very serious Fortran energy:

subroutine cunbdb6 (integer m1, integer m2, integer n, complex, dimension(*)
    x1, integer incx1, complex, dimension(*) x2, integer incx2, complex,
    dimension(ldq1,*) q1, integer ldq1, complex, dimension(ldq2,*) q2,
    integer ldq2, complex, dimension(*) work, integer lwork, integer info)

CUNBDB6 is here to orthogonalize things, and honestly? She ate.

Purpose

CUNBDB6 orthogonalizes the column vector

X = [ X1 ]
    [ X2 ]

with respect to the columns of

Q = [ Q1 ] .
    [ Q2 ]

The columns of Q must be orthonormal. The orthogonalized vector will be zero if and only if it lies entirely in the range of Q.

The projection is computed with at most two iterations of the classical Gram-Schmidt algorithm, see:

• L. Giraud, J. Langou, M. Rozložník.
• 2002. CERFACS Technical Report No. TR/PA/02/33. URL: https://www.cerfacs.fr/algor/reports/2002/TR_PA_02_33.pdf

Parameters

• M1 — M1 is INTEGER. The dimension of X1 and the number of rows in Q1. 0 <= M1. 🫶
• M2 — M2 is INTEGER. The dimension of X2 and the number of rows in Q2. 0 <= M2.
• N — N is INTEGER. The number of columns in Q1 and Q2. 0 <= N.
• X1 — X1 is COMPLEX array, dimension (M1). On entry, the top part of the vector to be orthogonalized. On exit, the top part of the projected vector. ✨
• INCX1 — INCX1 is INTEGER. Increment for entries of X1.
• X2 — X2 is COMPLEX array, dimension (M2). On entry, the bottom part of the vector to be orthogonalized. On exit, the bottom part of the projected vector. 🌸
• INCX2 — INCX2 is INTEGER. Increment for entries of X2.
• Q1 — Q1 is COMPLEX array, dimension (LDQ1, N). The top part of the orthonormal basis matrix. 👑
• LDQ1 — LDQ1 is INTEGER. The leading dimension of Q1. LDQ1 >= M1.
• Q2 — Q2 is COMPLEX array, dimension (LDQ2, N). The bottom part of the orthonormal basis matrix.
• LDQ2 — LDQ2 is INTEGER. The leading dimension of Q2. LDQ2 >= M2.
• WORK — WORK is COMPLEX array, dimension (LWORK). 🧚
• LWORK — LWORK is INTEGER. The dimension of the array WORK. LWORK >= N.
• INFO — INFO is INTEGER.
  • = 0: successful exit. 🎀
  • < 0: if INFO = -i, the i-th argument had an illegal value. 💀

Author

• Univ. of Tennessee
• Univ. of California Berkeley
• Univ. of Colorado Denver
• NAG Ltd.

Definition at line 157 of file cunbdb6.f.

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👑 Author 👑

Generated automatically by Doxygen for LAPACK from the source code.

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That's the whole page, bestie — LAPACK Version 3.12.0, source SRC/cunbdb6.f(3), and the footer date field is literally not listed on this page. Bye bestie! 💖💅🦋