SDRVPB(3)

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

okay so this is from the Library Functions Manual, and the file it lives in is literally:

/home/abuild/rpmbuild/BUILD/lapack-static-3.12.0-build/lapack-3.12.0/TESTING/LIN/sdrvpb.f

yes that's a real path, no I did not make it up, and yes it's giving "compiled on someone's very tired build server" energy 🫶

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✨ SYNOPSIS ✨

Functions/Subroutines

subroutine SDRVPB (dotype, nn, nval, nrhs, thresh, tsterr, nmax, a,
    afac, asav, b, bsav, x, xact, s, work, rwork, iwork, nout)

SDRVPB. that's it. that's the subroutine. iconic behavior honestly 👑

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🦋 Function/Subroutine Documentation 🦋

subroutine SDRVPB (logical, dimension( * ) dotype, integer nn, integer,
    dimension( * ) nval, integer nrhs, real thresh, logical tsterr, integer
    nmax, real, dimension( * ) a, real, dimension( * ) afac, real, dimension(
    * ) asav, real, dimension( * ) b, real, dimension( * ) bsav, real,
    dimension( * ) x, real, dimension( * ) xact, real, dimension( * ) s, real,
    dimension( * ) work, real, dimension( * ) rwork, integer, dimension( * )
    iwork, integer nout)

SDRVPB 💫

🎯 Purpose

!> !> SDRVPB tests the driver routines SPBSV and -SVX. !>

so yeah, it's a test driver. it's out here vibe-checking SPBSV and -SVX. lowkey the main character of the LAPACK testing suite for positive-definite banded solves 🎀

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🌸 Parameters 🌸

• DOTYPE — DOTYPE is LOGICAL array, dimension (NTYPES). The matrix types to be used for testing. Matrices of type j (for 1 <= j <= NTYPES) are used for testing if DOTYPE(j) = .TRUE.; if DOTYPE(j) = .FALSE., then type j is not used. it's literally a lil to-do list of which matrix types get to come to the party 💅
• NN — NN is INTEGER. The number of values of N contained in the vector NVAL. like, how many sizes are we testing, bestie.
• NVAL — NVAL is INTEGER array, dimension (NN). The values of the matrix dimension N. the whole roster of sizes, slay 📏
• NRHS — NRHS is INTEGER. The number of right hand side vectors to be generated for each linear system. how many RHS besties are we bringing to each solve.
• THRESH — THRESH is REAL. The threshold value for the test ratios. A result is included in the output file if RESULT >= THRESH. To have every test ratio printed, use THRESH = 0. so if you're nosy and want the full tea, set it to zero 🍵
• TSTERR — TSTERR is LOGICAL. Flag that indicates whether error exits are to be tested. do we test the error paths or not, that's the question.
• NMAX — NMAX is INTEGER. The maximum value permitted for N, used in dimensioning the work arrays. the ceiling, the limit, the "no we literally cannot go bigger than this" number.
• A — A is REAL array, dimension (NMAX*NMAX).
• AFAC — AFAC is REAL array, dimension (NMAX*NMAX).
• ASAV — ASAV is REAL array, dimension (NMAX*NMAX).
• B — B is REAL array, dimension (NMAX*NRHS).
• BSAV — BSAV is REAL array, dimension (NMAX*NRHS).
• X — X is REAL array, dimension (NMAX*NRHS).
• XACT — XACT is REAL array, dimension (NMAX*NRHS).
• S — S is REAL array, dimension (NMAX).
• WORK — WORK is REAL array, dimension (NMAX*max(3,NRHS)).
• RWORK — RWORK is REAL array, dimension (NMAX+2*NRHS).
• IWORK — IWORK is INTEGER array, dimension (NMAX).
• NOUT — NOUT is INTEGER. The unit number for output. where the results get printed, i.e. where the gossip gets published 📰

fr fr do not mess up those array dimensions, they are exactly that size and the compiler will simply not forgive you 😭

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👑 Author

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

absolute legends, all of them 🫡

Definition at line 161 of file sdrvpb.f.

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⭐ Author (again)

Generated automatically by Doxygen for LAPACK from the source code. not a human, just a doc generator doing its thing, and honestly? it ate 🤖✨

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and that's the page!! thanks for coming to my TED talk, go test your banded positive-definite solvers, drink some water, and remember: THRESH = 0 if you want all the results 💖

LAPACK, Version 3.12.0 — logged from /home/abui...IN/sdrvpb.f(3), with love (and a lot of build paths) 🎀