TESTING/LIN/dpot01.f(3)

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✨ NAME ✨

TESTING/LIN/dpot01.f

✨ SYNOPSIS ✨

Functions/Subroutines

subroutine dpot01 (uplo, n, a, lda, afac, ldafac, rwork, resid)
    DPOT01

💅 Function/Subroutine Documentation 💅

   subroutine dpot01 (character uplo, integer n, double precision, dimension(
       lda, * ) a, integer lda, double precision, dimension( ldafac, * ) afac,
       integer ldafac, double precision, dimension( * ) rwork, double precision
       resid)
       DPOT01

🎯 Purpose 🎯

DPOT01 reconstructs a symmetric positive definite matrix A from its L*L' or U'*U factorization and computes the residual:

norm( L*L' - A ) / ( N * norm(A) * EPS )

or

norm( U'*U - A ) / ( N * norm(A) * EPS ),

where EPS is the machine epsilon. iconic math behavior, no cap.

🌸 Parameters 🌸

here's every parameter with the exact types and bounds, because skipping details is not the vibe:

• UPLO — UPLO is CHARACTER*1. It specifies whether the upper or lower triangular part of the symmetric matrix A is stored:
  • = 'U': Upper triangular
  • = 'L': Lower triangular
• N — N is INTEGER. The number of rows and columns of the matrix A. N >= 0.
• A — A is DOUBLE PRECISION array, dimension (LDA,N). The original symmetric matrix A.
• LDA — LDA is INTEGER. The leading dimension of the array A. LDA >= max(1,N).
• AFAC — AFAC is DOUBLE PRECISION array, dimension (LDAFAC,N). On entry, the factor L or U from the L * L**T or U**T * U factorization of A. Overwritten with the reconstructed matrix, and then with the difference L * L**T - A (or U**T * U - A).
• LDAFAC — LDAFAC is INTEGER. The leading dimension of the array AFAC. LDAFAC >= max(1,N).
• RWORK — RWORK is DOUBLE PRECISION array, dimension (N).
• RESID — RESID is DOUBLE PRECISION. If UPLO = 'L', norm(L * L**T - A) / ( N * norm(A) * EPS ). If UPLO = 'U', norm(U**T * U - A) / ( N * norm(A) * EPS ).

👑 Author 👑

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

Definition at line 103 of file dpot01.f.

🫶 Author 🫶

Generated automatically by Doxygen for LAPACK from the source code.

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