SRC/zhetri_rook.f(3)

💖 SRC/zhetri_rook.f(3) 💖

okay bestie, welcome to this page from the Library Functions Manual — it's all about SRC/zhetri_rook.f, the zhetri_rook subroutine. Grab a boba, because this is literally the inverse-of-a-Hermitian-indefinite-matrix moment. ✨

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🌸 NAME 🌸

SRC/zhetri_rook.f

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✨ SYNOPSIS ✨

🧚 Functions/Subroutines

subroutine zhetri_rook (uplo, n, a, lda, ipiv, work, info)

and the full documented signature is:

subroutine zhetri_rook (character uplo, integer n, complex*16, dimension(
       lda, * ) a, integer lda, integer, dimension( * ) ipiv, complex*16,
       dimension( * ) work, integer info)

The synopsis one-liner says — exact words, no edits: ZHETRI_ROOK computes the inverse of HE matrix using the factorization obtained with the bounded Bunch-Kaufman (rook")diagonalpivotingmethod. 👑

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🛠️ Function/Subroutine Documentation 🛠️

🎯 Purpose:

ZHETRI_ROOK computes the inverse of a complex Hermitian indefinite matrix A using the factorization A = U*D*U**H or A = L*D*L**H computed by ZHETRF_ROOK. 💅

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🎀 Parameters 🎀

• UPLO — CHARACTER*1. Tells you whether the details of the factorization are stored as an upper or lower triangular matrix. The values are exactly: = 'U': Upper triangular, form is A = U*D*U**H; and = 'L': Lower triangular, form is A = L*D*L**H.
• N — INTEGER. The order of the matrix A. N >= 0.
• A — COMPLEX*16 array, dimension (LDA,N). On entry, it's the block diagonal matrix D and the multipliers used to obtain the factor U or L as computed by ZHETRF_ROOK. On exit, if INFO = 0, it's the (Hermitian) inverse of the original matrix. If UPLO = 'U', the upper triangular part of the inverse is formed and the part of A below the diagonal is not referenced; if UPLO = 'L', the lower triangular part of the inverse is formed and the part of A above the diagonal is not referenced. 🌈
• LDA — INTEGER. The leading dimension of the array A. LDA >= max(1,N).
• IPIV — INTEGER array, dimension (N). Details of the interchanges and the block structure of D as determined by ZHETRF_ROOK.
• WORK — COMPLEX*16 array, dimension (N). 🫶
• INFO — INTEGER. Here's the status tea:
  • = 0: successful exit
  • < 0: if INFO = -i, the i-th argument had an illegal value
  • > 0: if INFO = i, D(i,i) = 0; the matrix is singular and its inverse could not be computed.

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👑 Author

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

🌸 Contributors:

• November 2013, Igor Kozachenko, Computer Science Division, University of California, Berkeley
• September 2007, Sven Hammarling, Nicholas J. Higham, Craig Lucas, School of Mathematics, University of Manchester

📍 Definition

Definition at line 127 of file zhetri_rook.f.

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🤖 Author

Generated automatically by Doxygen for LAPACK from the source code.

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okay that's the whole page, bestie 💖 cute footer sign-off: LAPACK — Version 3.12.0 — SRC/zhetri_rook.f(3). mwah 💅🎀