ZLARZB(3)

💖 NAME 💖

This page is zlarzb.f(3) from the Library Functions Manual — path bestie: /home/abui...RC/zlarzb.f(3). ngl, it's the home of ZLARZB, and yes the filename is the whole NAME section. lowkey iconic. 💅

🌸 SYNOPSIS 🌸

🌟 Functions/Subroutines 🌟

       subroutine ZLARZB (side, trans, direct, storev, m, n, k, l, v, ldv, t,
           ldt, c, ldc, work, ldwork)

ZLARZB applies a block reflector or its conjugate-transpose to a general matrix. That's the one-liner, slay, no cap. ✨

✨ Function/Subroutine Documentation ✨

💅 subroutine ZLARZB 💅

   subroutine ZLARZB (character side, character trans, character direct,
       character storev, integer m, integer n, integer k, integer l,
       complex*16, dimension( ldv, * ) v, integer ldv, complex*16, dimension(
       ldt, * ) t, integer ldt, complex*16, dimension( ldc, * ) c, integer ldc,
       complex*16, dimension( ldwork, * ) work, integer ldwork)

ZLARZB applies a block reflector or its conjugate-transpose to a general matrix. Obsessed with the clarity. 🫶

🎯 Purpose: 🎯

okay so the literal purpose: ZLARZB applies a complex block reflector H or its transpose H**H to a complex distributed M-by-N C from the left or the right. It's giving block-reflector main character energy, fr fr.

⚠️ Currently, only STOREV = 'R' and DIRECT = 'B' are supported. That's the vibe check: other combos are not yet on the menu. 😭

🧚 Parameters 🧚

• SIDE — SIDE is CHARACTER*1
  • = 'L': apply H or H**H from the Left
  • = 'R': apply H or H**H from the Right
• TRANS — TRANS is CHARACTER*1
  • = 'N': apply H (No transpose)
  • = 'C': apply H**H (Conjugate transpose)
• DIRECT — DIRECT is CHARACTER*1. Indicates how H is formed from a product of elementary reflectors:
  • = 'F': H = H(1) H(2) . . . H(k) (Forward, not supported yet)
  • = 'B': H = H(k) . . . H(2) H(1) (Backward)
• STOREV — STOREV is CHARACTER*1. Indicates how the vectors which define the elementary reflectors are stored:
  • = 'C': Columnwise (not supported yet)
  • = 'R': Rowwise
• M — M is INTEGER. The number of rows of the matrix C.
• N — N is INTEGER. The number of columns of the matrix C.
• K — K is INTEGER. The order of the matrix T (= the number of elementary reflectors whose product defines the block reflector).
• L — L is INTEGER. The number of columns of the matrix V containing the meaningful part of the Householder reflectors. If SIDE = 'L', M >= L >= 0; if SIDE = 'R', N >= L >= 0.
• V — V is COMPLEX*16 array, dimension (LDV,NV). If STOREV = 'C', NV = K; if STOREV = 'R', NV = L.
• LDV — LDV is INTEGER. The leading dimension of the array V. If STOREV = 'C', LDV >= L; if STOREV = 'R', LDV >= K.
• T — T is COMPLEX*16 array, dimension (LDT,K). The triangular K-by-K matrix T in the representation of the block reflector.
• LDT — LDT is INTEGER. The leading dimension of the array T. LDT >= K.
• C — C is COMPLEX*16 array, dimension (LDC,N). On entry, the M-by-N matrix C. On exit, C is overwritten by H*C or H**H*C or C*H or C*H**H.
• LDC — LDC is INTEGER. The leading dimension of the array C. LDC >= max(1,M).
• WORK — WORK is COMPLEX*16 array, dimension (LDWORK,K).
• LDWORK — LDWORK is INTEGER. The leading dimension of the array WORK. If SIDE = 'L', LDWORK >= max(1,N); if SIDE = 'R', LDWORK >= max(1,M).

💖 Author 💖

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

🌈 Contributors: 🌈

A. Petitet, Computer Science Dept., Univ. of Tenn., Knoxville, USA

🦋 Further Details: 🦋

The whole further-details section in the original is literally just !>. not me expecting more deets. That's it, bestie. 💀

Definition at line 181 of file zlarzb.f.

✨ Author ✨

Generated automatically by Doxygen for LAPACK from the source code. So yes, the robots wrote this bit. 🤖💅

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Footer sign-off, bestie: LAPACK · Version 3.12.0 · /home/abui...RC/zlarzb.f(3) — that's the source/version, and the footer has no date listed, periodt. 💖✨