SRC/ctrti2.f(3)

💖 NAME 💖

SRC/ctrti2.f — hii bestie, welcome to the Library Functions Manual page for SRC/ctrti2.f(3). This is the whole vibe for the ctrti2 subroutine: the unblocked algorithm that computes the inverse of a triangular matrix. 💅✨

✨ SYNOPSIS ✨

Functions/Subroutines

• subroutine ctrti2 (uplo, diag, n, a, lda, info) — CTRTI2 computes the inverse of a triangular matrix (unblocked algorithm). 👑

🦋 Function/Subroutine Documentation 🦋

subroutine ctrti2 (character uplo, character diag, integer n, complex, dimension( lda, * ) a, integer lda, integer info)

CTRTI2 computes the inverse of a triangular matrix (unblocked algorithm). No cap, that's the whole function's main character energy. 💫

🌸 Purpose 🌸

Okay so the purpose is literally this: CTRTI2 computes the inverse of a complex upper or lower triangular matrix. 🫶

This is the Level 2 BLAS version of the algorithm. Periodt. 🔥

🎀 Parameters 🎀

• UPLO — UPLO is CHARACTER*1. This one specifies whether the matrix A is upper or lower triangular.
  • = 'U': Upper triangular
  • = 'L': Lower triangular
• DIAG — DIAG is CHARACTER*1. This tells you whether or not the matrix A is unit triangular.
  • = 'N': Non-unit triangular
  • = 'U': Unit triangular
• N — N is INTEGER. The order of the matrix A. N >= 0. 💖
• A — A is COMPLEX array, dimension (LDA,N). On entry, this is the triangular matrix A.
  • If UPLO = 'U', the leading n by n upper triangular part of the array A contains the upper triangular matrix, and the strictly lower triangular part of A is not referenced.
  • If UPLO = 'L', the leading n by n lower triangular part of the array A contains the lower triangular matrix, and the strictly upper triangular part of A is not referenced.
  • If DIAG = 'U', the diagonal elements of A are also not referenced and are assumed to be 1.

On exit, A holds the (triangular) inverse of the original matrix, in the same storage format. Slay. 💅

• LDA — LDA is INTEGER. The leading dimension of the array A. LDA >= max(1,N). 🦋
• INFO — INFO is INTEGER.
  • = 0: successful exit
  • < 0: if INFO = -k, the k-th argument had an illegal value

Bestie, that negative INFO is your little red flag that somebody passed a bad argument. 🙈

👑 Author 👑

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

Definition at line 109 of file ctrti2.f. 🎀

🌈 Author 🌈

Generated automatically by Doxygen for LAPACK from the source code. ✨

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Okay bestie, that's the whole page: it's from the Library Functions Manual, and this iconic little footer is giving LAPACK Version 3.12.0, page SRC/ctrti2.f(3). Mwah 💋✨🫶