CPOTRI(3)

🦋 CPOTRI(3) — cpotri.f, but make it make sense 💅

okay bestie so real talk: this page lives in the Library Functions Manual as /home/abui...RC/cpotri.f(3) — and the actual file it's dragging is /home/abuild/rpmbuild/BUILD/lapack-static-3.12.0-build/lapack-3.12.0/SRC/cpotri.f. yes that's the whole path, no I'm not shortening it, it's iconic in a chaotic way ✨

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✨ NAME ✨

/home/abuild/rpmbuild/BUILD/lapack-static-3.12.0-build/lapack-3.12.0/SRC/cpotri.f — that's our girl. one file, one job, one very long path 🎀

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🌸 SYNOPSIS 🌸

Functions/Subroutines

subroutine CPOTRI (uplo, n, a, lda, info)

CPOTRI — say her name 💖

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👑 Function/Subroutine Documentation 👑

subroutine CPOTRI (character uplo, integer n, complex, dimension( lda, * )
    a, integer lda, integer info)

CPOTRI. yeah. that's her. 🫶

💜 Purpose 💜

!> !> CPOTRI computes the inverse of a complex Hermitian positive definite !> matrix A using the Cholesky factorization A = U**H*U or A = L*L**H !> computed by CPOTRF. !>

so basically 😌 she takes a complex Hermitian positive definite matrix A, and she inverts it, using the Cholesky factorization A = U**H*U or A = L*L**H that CPOTRF already computed for you. teamwork fr fr 🌈

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🎀 Parameters 🎀

• UPLO — UPLO is CHARACTER*1. which triangle of A are we working with, bestie? pick one 🔥
  • = 'U': Upper triangle of A is stored;
  • = 'L': Lower triangle of A is stored.
• N — N is INTEGER. the order of the matrix A. and N >= 0, non-negotiable ✋
  • The order of the matrix A. N >= 0.
• A — A is COMPLEX array, dimension (LDA,N). the main character, honestly 💅
  • On entry: the triangular factor U or L from the Cholesky factorization A = U**H*U or A = L*L**H, as computed by CPOTRF.
  • On exit: the upper or lower triangle of the (Hermitian) inverse of A, overwriting the input factor U or L. not me gaslighting your input array 😭 it's gone, she's different now.
• LDA — LDA is INTEGER. the leading dimension of the array A. LDA >= max(1,N). do not test her on this one 🚨
  • The leading dimension of the array A. LDA >= max(1,N).
• INFO — INFO is INTEGER. the vibe check at the end ✨
  • = 0: successful exit — she ate and left no crumbs 🍓
  • < 0: if INFO = -i, the i-th argument had an illegal value — someone typed something cursed 🙈
  • > 0: if INFO = i, the (i,i) element of the factor U or L is zero, and the inverse could not be computed. 💀 big oof, the math said no.

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🌟 Author 🌟

genuinely a whole squad wrote this, show some respect 🫡

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

⭐ Definition at line 94 of file cpotri.f.

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💖 the sign-off 💖

this page was generated automatically by Doxygen for LAPACK from the source code — so nobody hand-wrote the boring parts, the robot did 🤖✨

and it's stamped LAPACK Version 3.12.0, arriving with that /home/abui...RC/cpotri.f(3) energy in the corner. that's the whole page, bestie — go invert something Hermitian and positive definite, and slay 💅🌈👑