DLATB5(3)

💅 DLATB5(3) — bestie, it's the LAPACK matrix-generator parameter girly

okay so real talk, this is a page from the dlatb5.f(3) manual (the one that lives at /home/abui...IN/dlatb5.f(3)), and it's literally just one little subroutine that sets up the vibes for matrix generation. no cap, she's a helper. but she's iconic at it. 🎀

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✨ SYNOPSIS ✨

Functions/Subroutines

• subroutine DLATB5 (path, imat, n, type, kl, ku, anorm, mode, cndnum, dist) — that's her!! that's the whole girl!!
• DLATB5 — she also answers to just her name, main character energy fr 💅

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🦋 Function/Subroutine Documentation 🦋

subroutine DLATB5 (character*3 path, integer imat, integer n, character
    type, integer kl, integer ku, double precision anorm, integer mode,
    double precision cndnum, character dist)

DLATB5 — again. she contains multitudes. 💖

🌸 Purpose:

!>
!> DLATB5 sets parameters for the matrix generator based on the type
!> of matrix to be generated.
!>

so like. she doesn't make the matrix. she sets the parameters so the matrix generator knows what's up. think of her as the group chat admin who makes the plans, and everyone else actually shows up. she ate that. 🔥

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🧚 Parameters 🧚

• PATH

!>          PATH is CHARACTER*3
!>          The LAPACK path name.
!>

three characters, that's all she needs. it's the LAPACK path name. short king behavior honestly 🫶

• IMAT

!>          IMAT is INTEGER
!>          An integer key describing which matrix to generate for this
!>          path.
!>

an integer key — the little ID badge that says which matrix we're generating for this path. lowkey the most important number here ngl 👑

• N

!>          N is INTEGER
!>          The number of rows and columns in the matrix to be generated.
!>

rows and columns, both. square queen. it's giving symmetry (but only if you asked for 'S', more on that in a sec) 📐✨

• TYPE

!>          TYPE is CHARACTER*1
!>          The type of the matrix to be generated:
!>          = 'S':  symmetric matrix
!>          = 'P':  symmetric positive (semi)definite matrix
!>          = 'N':  nonsymmetric matrix
!>

one single character, three whole personalities:

• 'S' → symmetric matrix 🪞
• 'P' → symmetric positive (semi)definite matrix ✨ (the parentheses are doing a lot of work there, respect)
• 'N' → nonsymmetric matrix 💀 (chaotic, no notes)

• KL

!>          KL is INTEGER
!>          The lower band width of the matrix to be generated.
!>

the lower band width. she's down there. holding it down. ⬇️

• KU

!>          KU is INTEGER
!>          The upper band width of the matrix to be generated.
!>

the upper band width. counterpart to KL, obviously. they're a matched set, iykyk 🌈

• ANORM

!>          ANORM is DOUBLE PRECISION
!>          The desired norm of the matrix to be generated.  The diagonal
!>          matrix of singular values or eigenvalues is scaled by this
!>          value.
!>

DOUBLE PRECISION because she's precise and she's not sorry about it 💅 this is the desired norm — and here's the tea: the diagonal matrix of singular values or eigenvalues gets scaled by this value. so she's not just a vibe, she's a multiplier. periodt 🍓

• MODE

!>          MODE is INTEGER
!>          A key indicating how to choose the vector of eigenvalues.
!>

a key that says how to choose the vector of eigenvalues. different key, different selection strategy. choose your fighter 🎀

• CNDNUM

!>          CNDNUM is DOUBLE PRECISION
!>          The desired condition number.
!>

DOUBLE PRECISION again, because the condition number deserves the good treatment. it's the desired condition number — manifestation era ✨🦋

• DIST

!>          DIST is CHARACTER*1
!>          The type of distribution to be used by the random number
!>          generator.
!>

one character telling the random number generator what distribution to use. yes she's controlling the RNG's whole aesthetic. someone has to 🌈

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👑 Author

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

literally a whole squad. four institutions for one parameters subroutine. we love a collaborative slay 🫶💜

Definition at line 112 of file dlatb5.f. go read her in the wild, she's right there 💖

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🌟 Author

Generated automatically by Doxygen for LAPACK from the source code. (yes, a robot wrote this. and honestly? she understood the assignment 🤖✨)

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heads up bestie: this page is auto-generated documentation — the !> blocks above are the actual source comments, so treat them as the real spec. don't go inventing behavior that isn't written there, ok? 💀

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and that's the whole page!! mwah 💋 — with love from the LAPACK crew, Version 3.12.0, dated /home/abui...IN/dlatb5.f(3). go off, DLATB5. 🎀💅✨