CPPCON(3)

CPPCON(3) 💅✨

okay so bestie, welcome to this page from the Library Functions Manual. We're doing CPPCON(3) today — it's a LAPACK thing, it lives in a .f file, and I'm gonna give you every single detail with zero skips. Periodt.

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🌸 NAME 🌸

The NAME on this page is literally the source path, bestie: /home/abuild/rpmbuild/BUILD/lapack-static-3.12.0-build/lapack-3.12.0/SRC/cppcon.f. That's it. That's the name. 💖

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✨ SYNOPSIS ✨

🧚 Functions/Subroutines 🧚

Here's the callable, exactly as written:

   subroutine CPPCON (uplo, n, ap, anorm, rcond, work, rwork, info)
           CPPCON

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💖 Function/Subroutine Documentation 💖

Full signature with types and dimensions — copy/paste safe, no cap:

   subroutine CPPCON (character uplo, integer n, complex, dimension( * ) ap,
       real anorm, real rcond, complex, dimension( * ) work, real, dimension( *
       ) rwork, integer info)
       CPPCON

🎀 Purpose 🎀

CPPCON estimates the reciprocal of the condition number (in the 1-norm) of a complex Hermitian positive definite packed matrix using the Cholesky factorization A = U**H*U or A = L*L**H computed by CPPTRF.

An estimate is obtained for norm(inv(A)), and the reciprocal of the condition number is computed as RCOND = 1 / (ANORM * norm(inv(A))).

🌈 Parameters 🌈

💜 UPLO

UPLO is CHARACTER*1.

• = 'U': upper triangle of A is stored;
• = 'L': lower triangle of A is stored.

🦋 N

N is INTEGER. The order of the matrix A. N >= 0.

🍓 AP

AP is COMPLEX array, dimension (N*(N+1)/2). The triangular factor U or L from the Cholesky factorization A = U**H*U or A = L*L**H, packed columnwise in a linear array. The j-th column of U or L is stored in the array AP as follows:

• if UPLO = 'U', AP(i + (j-1)*j/2) = U(i,j) for 1<=i<=j;
• if UPLO = 'L', AP(i + (j-1)*(2n-j)/2) = L(i,j) for j<=i<=n.

💜 ANORM

ANORM is REAL. The 1-norm (or infinity-norm) of the Hermitian matrix A.

🎀 RCOND

RCOND is REAL. The reciprocal of the condition number of the matrix A, computed as RCOND = 1/(ANORM * AINVNM), where AINVNM is an estimate of the 1-norm of inv(A) computed in this routine.

🌸 WORK

WORK is COMPLEX array, dimension (2*N).

⭐ RWORK

RWORK is REAL array, dimension (N).

👑 INFO

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 117 of file cppcon.f.

👑 Author 👑

Generated automatically by Doxygen for LAPACK from the source code.

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okay bestie, that's the whole page. This one is LAPACK Version 3.12.0, and the footer path is /home/abui...RC/cppcon.f(3). Mwah 💋✨