TESTING/LIN/clarhs.f(3)

🌸 NAME 🌸

okay so this page is from the Library Functions Manual, and it’s literally all about TESTING/LIN/clarhs.f — the CLARHS subroutine. no cap, bestie 💖

✨ SYNOPSIS ✨

🧚 Functions/Subroutines 🧚

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

💅 Function/Subroutine Documentation 💅

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

🎀 Purpose 🎀

So CLARHS chooses a whole 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. it’s giving “test-matrix setup main character energy” fr fr 🔥

🌈 Parameters 🌈

• PATH — PATH is CHARACTER*3. it tells you the type of the complex matrix A. 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. it specifies how the exact solution X will be determined:
  • = 'N': New solution; generate a random X.
  • = 'C': Computed; use value of X on entry.
• 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)
• 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

• NRHS — NRHS is INTEGER. the number of right hand side vectors in the system A*X = B. 💖
• A — A is COMPLEX 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 an input/output COMPLEX 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 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 CLATMS). modified on exit. not me forgetting that it changes 💀
• 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 206 of file clarhs.f.

🌟 Author 🌟

Generated automatically by Doxygen for LAPACK from the source code.

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cute little sign-off bestie: this is LAPACK Version 3.12.0, page TESTING/LIN/clarhs.f(3) — slay, bye 💅💖