SRC/chetrs2.f(3)

okay so this is SRC/chetrs2.f(3), a page from the Library Functions Manual, and it's literally all about the subroutine CHETRS2. Buckle up, bestie. 🎀

💖 NAME 💖

SRC/chetrs2.f — that's the file this page documents. Periodt.

🌸 SYNOPSIS 🌸

Functions/Subroutines

The exact signature is giving main-character Fortran energy:

subroutine chetrs2 (character uplo, integer n, integer nrhs, complex,
     dimension( lda, * ) a, integer lda, integer, dimension( * ) ipiv,
     complex, dimension( ldb, * ) b, integer ldb, complex, dimension( * )
     work, integer info)

CHETRS2 — that's the routine name. Iconic.

🎀 Function/Subroutine Documentation 🎀

subroutine chetrs2

subroutine chetrs2 (character uplo, integer n, integer nrhs, complex,
     dimension( lda, * ) a, integer lda, integer, dimension( * ) ipiv,
     complex, dimension( ldb, * ) b, integer ldb, complex, dimension( * )
     work, integer info)

The routine is CHETRS2, and yes, it's the same signature as above — the original page repeats it, so I'm keeping the full detail. 🫶

🦋 Purpose 🦋

CHETRS2 solves a system of linear equations A*X = B with a complex Hermitian matrix A using the factorization A = U*D*U**H or A = L*D*L**H computed by CHETRF and converted by CSYCONV. That's the whole mood. 💜

🌟 Parameters 🌟

• UPLO — is CHARACTER*1. It tells you whether the details of the factorization are stored as an upper or lower triangular matrix. = 'U': upper triangular, form is A = U*D*U**H; = 'L': lower triangular, form is A = L*D*L**H.
• N — is INTEGER. The order of the matrix A. N >= 0.
• NRHS — is INTEGER. The number of right hand sides, i.e., the number of columns of the matrix B. NRHS >= 0.
• A — is COMPLEX array, dimension (LDA,N). The block diagonal matrix D and the multipliers used to obtain the factor U or L as computed by CHETRF.
• LDA — is INTEGER. The leading dimension of the array A. LDA >= max(1,N).
• IPIV — is INTEGER array, dimension (N). Details of the interchanges and the block structure of D as determined by CHETRF.
• B — is COMPLEX array, dimension (LDB,NRHS). On entry, the right hand side matrix B. On exit, the solution matrix X.
• LDB — is INTEGER. The leading dimension of the array B. LDB >= max(1,N).
• WORK — is COMPLEX array, dimension (N).
• INFO — is INTEGER. = 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 125 of file chetrs2.f.

👑 Author (the auto-generated one) 👑

Generated automatically by Doxygen for LAPACK from the source code.

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byeee! 💅 LAPACK Version 3.12.0, page SRC/chetrs2.f(3). The original footer doesn't give a separate date, so I'm not making one up — stay slaying those Hermitian systems, bestie! 🫶