lis_solver...esidualnorm(3)

✨ lis_solver_get_residualnorm ✨

okay bestie, welcome to the Lis Library Functions corner of the manual 💖 this one's a lil function called lis_solver_get_residualnorm, and it's here to do one very specific, very slay thing.

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🎀 NAME 🎀

lis_solver_get_residualnorm — calculate the relative residual norm from the solution 💅

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🦋 SYNOPSIS 🦋

#include "lis.h"

LIS_INT lis_solver_get_residualnorm(LIS_SOLVER solver, LIS_INT
*residual);

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🌸 DESCRIPTION 🌸

so basically, this function takes your solution x and computes the relative residual norm, which is literally this:

||b - Ax||_2/||b||_2

like. that's the whole vibe. you solved the thing, now you wanna know how good the solve actually was, and this is the number that tells you 🔥

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💜 INPUT 💜

• solver — the solver, bestie. that's the one you hand over.

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🫶 OUTPUT 🫶

• residual — the relative residual norm ||b - Ax||_2/||b||_2 ✨

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👑 EXIT STATUS 👑

these are the exit values you might get back:

• 0 — the process is normally terminated 🥳 everything ate, no crumbs.
• unspecified — an error occurred 😭 it's giving chaos, not in a fun way.

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🌈 SEE ALSO 🌈

• lis(3)
• http://www.ssisc.org/lis/

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fr fr, that's the whole page. no notes, no cap 💅

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and that's a wrap, my love 🎀 this was brought to you by the Man Page of 6 Sep 2012, from the Lis Library Functions lineup. stay iconic, stay solving, mwah 🫶💖✨