CPPT03(3)

πŸ“¦ version 3.12.0, in opensuse-leap 16.0

πŸ’– CPPT03(3) β€” Library Functions Manual energy πŸ’–

okay so this is the CPPT03(3) page, and the header says it's from the Library Functions Manual (title vibe: cppt03.f(3)). bestie, we're about to get into some Hermitian packed-matrix residual math, and honestly? it's giving precise. πŸ’…


🌸 NAME 🌸

/home/abuild/rpmbuild/BUILD/lapack-static-3.12.0-build/lapack-3.12.0/TESTING/LIN/cppt03.f


✨ SYNOPSIS ✨

🫢 Functions/Subroutines 🫢

subroutine CPPT03 (uplo, n, a, ainv, work, ldwork, rwork, rcond, resid)

CPPT03


πŸ› οΈ Function/Subroutine Documentation πŸ› οΈ

subroutine CPPT03 (character uplo, integer n, complex, dimension( * ) a,
    complex, dimension( * ) ainv, complex, dimension( ldwork, * ) work,
    integer ldwork, real, dimension( * ) rwork, real rcond, real resid)

CPPT03


🎯 Purpose 🎯

CPPT03 computes the residual for a Hermitian packed matrix times its inverse, and the formula is literally this:

norm( I - A*AINV ) / ( N * norm(A) * norm(AINV) * EPS ),

where EPS is the machine epsilon. no cap, that's the whole mission. 🌟


🧾 Parameters 🧾

  • UPLO β€” UPLO is CHARACTER*1; it says whether the upper or lower triangular part of the Hermitian matrix A is stored:
    • = 'U': Upper triangular
    • = 'L': Lower triangular
  • N β€” N is INTEGER; it's the number of rows and columns of the matrix A. Constraint: N >= 0.
  • A β€” A is COMPLEX array, dimension (N*(N+1)/2); this is the original Hermitian matrix A, stored as a packed triangular matrix.
  • AINV β€” AINV is COMPLEX array, dimension (N*(N+1)/2); this is the (Hermitian) inverse of the matrix A, stored as a packed triangular matrix.
  • WORK β€” WORK is COMPLEX array, dimension (LDWORK,N).
  • LDWORK β€” LDWORK is INTEGER; it's the leading dimension of the array WORK. Constraint: LDWORK >= max(1,N).
  • RWORK β€” RWORK is REAL array, dimension (N).
  • RCOND β€” RCOND is REAL; it's the reciprocal of the condition number of A, computed as ( 1/norm(A) ) / norm(AINV).
  • RESID β€” RESID is REAL; it's norm(I - A*AINV) / ( N * norm(A) * norm(AINV) * EPS ).

✍️ Author ✍️

Univ. of Tennessee

Univ. of California Berkeley

Univ. of Colorado Denver

NAG Ltd.


πŸ“Œ Definition at line πŸ“Œ

Definition at line 108 of file cppt03.f.


πŸ’Œ Author πŸ’Œ

Generated automatically by Doxygen for LAPACK from the source code.


mwah πŸ’‹ β€” signed off with glitter and good vibes: LAPACK, Version 3.12.0, and the footer path is /home/abui...IN/cppt03.f(3). πŸŽ€

πŸ“¦ where this page comes from