ZLARHS(3)

💅 zlarhs.f(3) — like, the whole manual page, bestie ✨

okay so real quick: this is zlarhs.f(3) from the LAPACK library functions manual, and it lives at /home/abuild/rpmbuild/BUILD/lapack-static-3.12.0-build/lapack-3.12.0/TESTING/LIN/zlarhs.f 🫶 that's literally the NAME section, that's it, that's the name. moving on 💖

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✨ SYNOPSIS ✨

🌸 Functions/Subroutines

subroutine ZLARHS (path, xtype, uplo, trans, m, n, kl, ku, nrhs, a, lda,
    x, ldx, b, ldb, iseed, info)

ZLARHS — that's the whole vibe, she's the function 🎀

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💜 Function/Subroutine Documentation 💜

subroutine ZLARHS (character*3 path, character xtype, character uplo,
    character trans, integer m, integer n, integer kl, integer ku, integer
    nrhs, complex*16, dimension( lda, * ) a, integer lda, complex*16,
    dimension( ldx, * ) x, integer ldx, complex*16, dimension( ldb, * ) b,
    integer ldb, integer, dimension( 4 ) iseed, integer info)

ZLARHS

🌈 Purpose 🌈

!> ZLARHS chooses a set of NRHS random solution vectors and sets !> up the right hand sides for the linear system !> op(A) * X = B, !> where op(A) = A, A**T, or A**H, depending on TRANS. !>

like, she's out here picking random solution vectors and building your right hand sides. iconic behavior honestly 👑

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💖 Parameters 💖

• PATH — so PATH is CHARACTER*3 and it's giving what kind of complex matrix is A, bestie. PATH may be given in any combination of upper and lower case. Valid paths include:
  • xGE: General m x n matrix
  • xGB: General banded matrix
  • xPO: Hermitian positive definite, 2-D storage
  • xPP: Hermitian positive definite packed
  • xPB: Hermitian positive definite banded
  • xHE: Hermitian indefinite, 2-D storage
  • xHP: Hermitian indefinite packed
  • xHB: Hermitian indefinite banded
  • xSY: Symmetric indefinite, 2-D storage
  • xSP: Symmetric indefinite packed
  • xSB: Symmetric indefinite banded
  • xTR: Triangular
  • xTP: Triangular packed
  • xTB: Triangular banded
  • xQR: General m x n matrix
  • xLQ: General m x n matrix
  • xQL: General m x n matrix
  • xRQ: General m x n matrix

where the leading character indicates the precision ✨ (iykyk)

• XTYPE — XTYPE is CHARACTER*1 and specifies how the exact solution X will be determined:
  • = 'N': New solution; generate a random X.
  • = 'C': Computed; use value of X on entry.

so either she makes one up for you or you bring your own, no in-between 🎀

• UPLO — UPLO is CHARACTER*1. Used only if A is symmetric or triangular; specifies whether the upper or lower triangular part of the matrix A is stored.
  • = 'U': Upper triangular
  • = 'L': Lower triangular
• TRANS — TRANS is CHARACTER*1. Used only if A is nonsymmetric; specifies the operation applied to the matrix A.
  • = 'N': B := A * X (No transpose)
  • = 'T': B := A**T * X (Transpose)
  • = 'C': B := A**H * X (Conjugate transpose)

three flavors, all valid, pick your fighter 💅

• M — M is INTEGER. The number of rows of the matrix A. M >= 0.
• N — N is INTEGER. The number of columns of the matrix A. N >= 0.
• KL — KL is INTEGER. Used only if A is a band matrix; specifies the number of subdiagonals of A if A is a general band matrix or if A is symmetric or triangular and UPLO = 'L'; specifies the number of superdiagonals of A if A is symmetric or triangular and UPLO = 'U'. 0 <= KL <= M-1.
• KU — KU is INTEGER. Used only if A is a general band matrix or if A is triangular.
  • If PATH = xGB, specifies the number of superdiagonals of A, and 0 <= KU <= N-1.
  • If PATH = xTR, xTP, or xTB, specifies whether or not the matrix has unit diagonal:
    • = 1: matrix has non-unit diagonal (default)
    • = 2: matrix has unit diagonal

two whole personality modes for one variable, she's versatile 😭

• NRHS — NRHS is INTEGER. The number of right hand side vectors in the system A*X = B.
• A — A is COMPLEX*16 array, dimension (LDA,N). The test matrix whose type is given by PATH.
• LDA — LDA is INTEGER. The leading dimension of the array A.
  • If PATH = xGB, LDA >= KL+KU+1.
  • If PATH = xPB, xSB, xHB, or xTB, LDA >= KL+1.
  • Otherwise, LDA >= max(1,M).
• X — X is or output) COMPLEX*16 array, dimension (LDX,NRHS). On entry, if XTYPE = 'C' (for 'Computed'), then X contains the exact solution to the system of linear equations. On exit, if XTYPE = 'N' (for 'New'), then X is initialized with random values. 🦋
• LDX — LDX is INTEGER. The leading dimension of the array X. If TRANS = 'N', LDX >= max(1,N); if TRANS = 'T', LDX >= max(1,M).
• B — B is COMPLEX*16 array, dimension (LDB,NRHS). The right hand side vector(s) for the system of equations, computed from B = op(A) * X, where op(A) is determined by TRANS.
• LDB — LDB is INTEGER. The leading dimension of the array B. If TRANS = 'N', LDB >= max(1,M); if TRANS = 'T', LDB >= max(1,N).
• ISEED — ISEED is INTEGER array, dimension (4). The seed vector for the random number generator (used in ZLATMS). Modified on exit. 🙈 heads up, she will touch your seed.
• INFO — INFO is INTEGER.
  • = 0: successful exit
  • < 0: if INFO = -i, the i-th argument had an illegal value

⚠️ bestie watch the signs: INFO = 0 is the slay outcome, and any negative INFO means argument number -i was being messy. no cap.

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👑 Author 👑

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

Definition at line 206 of file zlarhs.f.

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🌸 Author 🌸

Generated automatically by Doxygen for LAPACK from the source code. (yes the robot wrote this one, not me 💀)

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LAPACK — Version 3.12.0 — and that's the whole page from /home/abui...IN/zlarhs.f(3), mwah 💋 thanks for reading bestie, go call ZLARHS responsibly 🫶✨🎀