/home/abui...nvf_rook.f(3)

okay so bestie, this is the /home/abui...nvf_rook.f(3) page from the Library Functions Manual — and it’s fully about DSYCONVF_ROOK. Buckle up, it’s giving LAPACK conversion lore 💅

✨ NAME ✨

/home/abuild/rpmbuild/BUILD/lapack-static-3.12.0-build/lapack-3.12.0/SRC/dsyconvf_rook.f

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🌸 SYNOPSIS 🌸

🧚 Functions/Subroutines 🧚

• subroutine DSYCONVF_ROOK (uplo, way, n, a, lda, e, ipiv, info) — DSYCONVF_ROOK

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👑 Function/Subroutine Documentation 👑

Here’s the exact signature, no cap:

subroutine DSYCONVF_ROOK (character uplo, character way, integer n, double
    precision, dimension( lda, * ) a, integer lda, double precision,
    dimension( * ) e, integer, dimension( * ) ipiv, integer info)
    DSYCONVF_ROOK

💖 Purpose 💖

If parameter WAY = 'C': DSYCONVF_ROOK converts the factorization output format used in DSYTRF_ROOK provided on entry in parameter A into the factorization output format used in DSYTRF_RK (or DSYTRF_BK) that is stored on exit in parameters A and E. IPIV format for DSYTRF_ROOK and DSYTRF_RK (or DSYTRF_BK) is the same and is not converted.

If parameter WAY = 'R': DSYCONVF_ROOK performs the conversion in reverse direction, i.e. converts the factorization output format used in DSYTRF_RK (or DSYTRF_BK) provided on entry in parameters A and E into the factorization output format used in DSYTRF_ROOK that is stored on exit in parameter A. IPIV format for DSYTRF_ROOK and DSYTRF_RK (or DSYTRF_BK) is the same and is not converted.

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🎀 Parameters 🎀

• UPLO — UPLO is CHARACTER*1. Specifies whether the details of the factorization are stored as an upper or lower triangular matrix A.
  • = 'U': Upper triangular
  • = 'L': Lower triangular
• WAY — WAY is CHARACTER*1
  • = 'C': Convert
  • = 'R': Revert
• N — N is INTEGER. The order of the matrix A. N >= 0.
• A — A is DOUBLE PRECISION array, dimension (LDA,N).
  • 1) If WAY ='C':
    • On entry, contains factorization details in format used in DSYTRF_ROOK:
      • a) all elements of the symmetric block diagonal matrix D on the diagonal of A and on superdiagonal (or subdiagonal) of A, and
      • b) If UPLO = 'U': multipliers used to obtain factor U in the superdiagonal part of A. If UPLO = 'L': multipliers used to obtain factor L in the superdiagonal part of A.
    • On exit, contains factorization details in format used in DSYTRF_RK or DSYTRF_BK:
      • a) ONLY diagonal elements of the symmetric block diagonal matrix D on the diagonal of A, i.e. D(k,k) = A(k,k); (superdiagonal (or subdiagonal) elements of D are stored on exit in array E), and
      • b) If UPLO = 'U': factor U in the superdiagonal part of A. If UPLO = 'L': factor L in the subdiagonal part of A.
  • 2) If WAY ='R':
    • On entry, contains factorization details in format used in DSYTRF_RK or DSYTRF_BK:
      • a) ONLY diagonal elements of the symmetric block diagonal matrix D on the diagonal of A, i.e. D(k,k) = A(k,k); (superdiagonal (or subdiagonal) elements of D are stored on exit in array E), and
      • b) If UPLO = 'U': factor U in the superdiagonal part of A. If UPLO = 'L': factor L in the subdiagonal part of A.
    • On exit, contains factorization details in format used in DSYTRF_ROOK:
      • a) all elements of the symmetric block diagonal matrix D on the diagonal of A and on superdiagonal (or subdiagonal) of A, and
      • b) If UPLO = 'U': multipliers used to obtain factor U in the superdiagonal part of A. If UPLO = 'L': multipliers used to obtain factor L in the superdiagonal part of A.
• LDA — LDA is INTEGER. The leading dimension of the array A. LDA >= max(1,N).
• E — E is DOUBLE PRECISION array, dimension (N).
  • 1) If WAY ='C':
    • On entry, just a workspace.
    • On exit, contains the superdiagonal (or subdiagonal) elements of the symmetric block diagonal matrix D with 1-by-1 or 2-by-2 diagonal blocks, where If UPLO = 'U': E(i) = D(i-1,i), i=2:N, E(1) is set to 0; If UPLO = 'L': E(i) = D(i+1,i), i=1:N-1, E(N) is set to 0.
  • 2) If WAY ='R':
    • On entry, contains the superdiagonal (or subdiagonal) elements of the symmetric block diagonal matrix D with 1-by-1 or 2-by-2 diagonal blocks, where If UPLO = 'U': E(i) = D(i-1,i),i=2:N, E(1) not referenced; If UPLO = 'L': E(i) = D(i+1,i),i=1:N-1, E(N) not referenced.
    • On exit, is not changed.
• IPIV — IPIV is INTEGER array, dimension (N). On entry, details of the interchanges and the block structure of D as determined:
  1. by DSYTRF_ROOK, if WAY ='C';
  2. by DSYTRF_RK (or DSYTRF_BK), if WAY ='R'. The IPIV format is the same for all these routines. On exit, is not changed.
• INFO — INFO is INTEGER
  • = 0: successful exit
  • < 0: if INFO = -i, the i-th argument had an illegal value

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🌈 Author 🌈

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

🦋 Contributors 🦋

• November 2017, Igor Kozachenko, Computer Science Division, University of California, Berkeley

📍 Definition at line 196 of file dsyconvf_rook.f 📍

Author

Generated automatically by Doxygen for LAPACK from the source code.

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Okay that’s the whole page, bestie — footer vibes are LAPACK Version 3.12.0 and source /home/abui...nvf_rook.f(3) (no extra date in the original footer, just those). Bye, slay 💖✨