DTRTRI(3)

💅 NAME 💅

/home/abuild/rpmbuild/BUILD/lapack-static-3.12.0-build/lapack-3.12.0/SRC/dtrtri.f is the file this page is all about, bestie. This is the dtrtri.f(3) glow-up from the Library Functions Manual, and yes, it’s giving very much “triangular inverse main character energy.” 💖

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✨ SYNOPSIS ✨

🦋 Functions/Subroutines 🦋

subroutine DTRTRI (uplo, diag, n, a, lda, info)
    DTRTRI

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🧚 Function/Subroutine Documentation 🧚

subroutine DTRTRI (character uplo, character diag, integer n, double
     precision, dimension( lda, * ) a, integer lda, integer info)
    DTRTRI

🎯 Purpose 🎯

DTRTRI computes the inverse of a real upper or lower triangular matrix A. No cap, that’s the whole assignment. 💅

This is the Level 3 BLAS version of the algorithm. Built different, fr fr. 🔥

🌸 Parameters 🌸

• UPLO — is CHARACTER*1. = 'U': A is upper triangular; = 'L': A is lower triangular. Pick your triangle, bestie. 🎀
• DIAG — is CHARACTER*1. = 'N': A is non-unit triangular; = 'U': A is unit triangular. This is the diagonal vibe check. ✨
• N — is INTEGER. The order of the matrix A. N >= 0. Zero is allowed, she’s valid. 🫶
• A — is DOUBLE PRECISION array, dimension (LDA,N). On entry, 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, the (triangular) inverse of the original matrix, in the same storage format. She stores, she flips, she slays. 💀💖
• LDA — is INTEGER. The leading dimension of the array A. LDA >= max(1,N). Respect the leading dimension, periodt. 📏
• INFO — is INTEGER. = 0: successful exit. < 0: if INFO = -i, the i-th argument had an illegal value. > 0: if INFO = i, A(i,i) is exactly zero. The triangular matrix is singular and its inverse can not be computed. 🚨

Heads up: if INFO > 0, that diagonal zero means the inverse literally can not be computed. No amount of good vibes fixes a singular matrix, bestie. 😭

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👑 Author 👑

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

Definition at line 108 of file dtrtri.f. 📍

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📜 Author 📜

Generated automatically by Doxygen for LAPACK from the source code. The robot did the typing, we just added the sparkle. 🤖✨

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LAPACK Version 3.12.0 · source path /home/abui...RC/dtrtri.f(3) · date: not listed in this footer, so I’m not inventing one, bestie 😌💖