CSGT01(3)

💅 CSGT01(3) — like, the whole manual page, bestie

okay so this is from the Library Functions Manual and honestly? the page name is a whole path and a half: /home/abui...IG/csgt01.f(3). yes it's truncated. no we're not fixing it. it's giving "found in the LAPACK test suite" energy and we respect it 🎀

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✨ NAME ✨

/home/abuild/rpmbuild/BUILD/lapack-static-3.12.0-build/lapack-3.12.0/TESTING/EIG/csgt01.f

that's it. that's the name. it's a whole file path, it's loud, it's iconic, it's literally just where the source lives 🌸

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🦋 SYNOPSIS 🦋

Functions/Subroutines

• subroutine CSGT01 — ok so she takes (itype, uplo, n, m, a, lda, b, ldb, z, ldz, d, work, rwork, result) and she does exactly one job, which is checking your generalized eigenproblem decomposition. CSGT01.

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🔥 Function/Subroutine Documentation 🔥

subroutine CSGT01

here's the full glow-up signature, no edits, no cap:

subroutine CSGT01 (integer itype, character uplo, integer n, integer m,
    complex, dimension( lda, * ) a, integer lda, complex, dimension( ldb, *
    ) b, integer ldb, complex, dimension( ldz, * ) z, integer ldz, real,
    dimension( * ) d, complex, dimension( * ) work, real, dimension( * )
    rwork, real, dimension( * ) result)

CSGT01

💜 Purpose 💜

!> !> CSGT01 checks a decomposition of the form !> !> A Z = B Z D or !> A B Z = Z D or !> B A Z = Z D !> !> where A is a Hermitian matrix, B is Hermitian positive definite, !> Z is unitary, and D is diagonal. !> !> One of the following test ratios is computed: !> !> ITYPE = 1: RESULT(1) = | A Z - B Z D | / ( |A| |Z| n ulp ) !> !> ITYPE = 2: RESULT(1) = | A B Z - Z D | / ( |A| |Z| n ulp ) !> !> ITYPE = 3: RESULT(1) = | B A Z - Z D | / ( |A| |Z| n ulp ) !>

so basically: pick your flavor of A Z = B Z D-ish situation and she computes a test ratio for you. three whole forms. she ate 💅

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✨ Parameters ✨

ITYPE

!> ITYPE is INTEGER !> The form of the Hermitian generalized eigenproblem. !> = 1: A*z = (lambda)*B*z !> = 2: A*B*z = (lambda)*z !> = 3: B*A*z = (lambda)*z !>

which form are we testing today bestie, 1, 2, or 3 💀

UPLO

!> UPLO is CHARACTER*1 !> Specifies whether the upper or lower triangular part of the !> Hermitian matrices A and B is stored. !> = 'U': Upper triangular !> = 'L': Lower triangular !>

'U' for upper, 'L' for lower. pick a lane 🦋

N

!> N is INTEGER !> The order of the matrix A. N >= 0. !>

the order of A. and she said N >= 0, so no negativity allowed ✨

M

!> M is INTEGER !> The number of eigenvalues found. M >= 0. !>

how many eigenvalues you actually found. M >= 0 fr fr

A

!> A is COMPLEX array, dimension (LDA, N) !> The original Hermitian matrix A. !>

the original Hermitian queen herself, A 👑

LDA

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

leading dimension of A. LDA >= max(1,N), periodt.

B

!> B is COMPLEX array, dimension (LDB, N) !> The original Hermitian positive definite matrix B. !>

B!! the original Hermitian positive definite one. she has standards 🎀

LDB

!> LDB is INTEGER !> The leading dimension of the array B. LDB >= max(1,N). !>

leading dimension of B. LDB >= max(1,N).

Z

!> Z is COMPLEX array, dimension (LDZ, M) !> The computed eigenvectors of the generalized eigenproblem. !>

the computed eigenvectors. main character array honestly 🌟

LDZ

!> LDZ is INTEGER !> The leading dimension of the array Z. LDZ >= max(1,N). !>

leading dimension of Z. LDZ >= max(1,N), same rules as her sisters.

D

!> D is REAL array, dimension (M) !> The computed eigenvalues of the generalized eigenproblem. !>

the computed eigenvalues. real ones. literally and figuratively 💅

WORK

!> WORK is COMPLEX array, dimension (N*N) !>

complex workspace, dimension (N*N). she's doing the behind-the-scenes labor 🫶

RWORK

!> RWORK is REAL array, dimension (N) !>

real workspace, dimension (N). supporting role but essential, ngl.

RESULT

!> RESULT is REAL array, dimension (1) !> The test ratio as described above. !>

the moment we've all been waiting for: the test ratio itself, dimension (1), as described above. the vibe check of the whole operation 🌈

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🌸 Author 🌸

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

four whole institutions collaborated on this and honestly? teamwork makes the dream work ✨

Definition at line 150 of file csgt01.f.

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👑 Author 👑

Generated automatically by Doxygen for LAPACK from the source code.

(not a human author, a robot author, generated from the source. she's automated and thriving 🤖💖)

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okay that's the whole page and yes it was a lot of !> comment markers and we survived 🧚 and for the sign-off — this absolute artifact is LAPACK Version 3.12.0, dated/stamped with /home/abui...IG/csgt01.f(3), so like… go forth and singular-value-decompose responsibly bestie 💜🍓