SRC/cpotrs.f(3)

✨ SRC/cpotrs.f ✨

okay bestie, gather round, because this is the cpotrs.f manpage from the LAPACK library manual and it's lowkey iconic 💅 (the manual name is LAPACK, fr — we're in the Library Functions Manual, section 3)

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🦋 SYNOPSIS 🦋

Functions/Subroutines

• subroutine cpotrs (uplo, n, nrhs, a, lda, b, ldb, info) — CPOTRS

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🌸 Function/Subroutine Documentation 🌸

subroutine cpotrs (character uplo, integer n, integer nrhs, complex,
    dimension( lda, * ) a, integer lda, complex, dimension( ldb, * ) b,
    integer ldb, integer info)

CPOTRS — say it with me, bestie 🎀

💖 Purpose 💖

k so here's the tea ☕ — CPOTRS solves a system of linear equations A*X = B with a Hermitian positive definite matrix A using the Cholesky factorization A = U**H*U or A = L*L**H computed by CPOTRF. that's it, that's the whole vibe. it takes the factorization your girl CPOTRF already did and actually solves the thing. slay 💅

🌈 Parameters 🌈

• UPLO — UPLO is CHARACTER*1. it tells you which triangle of A is stored, and there are exactly two moods:
  • = 'U': Upper triangle of A is stored;
  • = 'L': Lower triangle of A is stored.
• N — N is INTEGER. the order of the matrix A. the rules are simple: N >= 0. no cap 🫶
• NRHS — NRHS is INTEGER. the number of right hand sides, i.e., the number of columns of the matrix B. and yes, NRHS >= 0 — that constraint is literally non-negotiable ✨
• A — A is COMPLEX array, dimension (LDA,N). this is the triangular factor U or L from the Cholesky factorization A = U**H*U or A = L*L**H, as computed by CPOTRF. it's giving "hand me the factorized version, I'll take it from here" 👑
• LDA — LDA is INTEGER. the leading dimension of the array A. and the boundary is LDA >= max(1,N). respect it 💀
• B — B is COMPLEX array, dimension (LDB,NRHS). on entry, the right hand side matrix B. on exit, the solution matrix X. so it's a glow-up situation — same array, new identity, main character energy 🌟
• LDB — LDB is INTEGER. the leading dimension of the array B. fun little rule: LDB >= max(1,N) 🎀
• INFO — INFO is INTEGER. the vibe check at the end:
  • = 0: successful exit ✨
  • < 0: if INFO = -i, the i-th argument had an illegal value 🙈

💜 Author 💜

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

Definition at line 109 of file cpotrs.f. 📍

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🧚 Author 🧚

Generated automatically by Doxygen for LAPACK from the source code. (yes bestie, a robot wrote the manpage, the algorithm wrote the math, and I'm just here making it cute 🫶)

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k that's the whole page, no gatekeeping 💖 LAPACK, Version 3.12.0, SRC/cpotrs.f(3) — go solve something, icon 🌸🦋💅