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

🎀 NAME 🎀

okay so this page is from the Library Functions Manual — manual name folded in right here, bestie. It’s all about:

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

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✨ SYNOPSIS ✨

Functions/Subroutines

       real function SLA_GERCOND (trans, n, a, lda, af, ldaf, ipiv, cmode, c,
           info, work, iwork)

SLA_GERCOND estimates the Skeel condition number for a general matrix. 💅

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💖 Function/Subroutine Documentation 💖

       real function SLA_GERCOND (character trans, integer n, real, dimension( lda,
       * ) a, integer lda, real, dimension( ldaf, * ) af, integer ldaf,
       integer, dimension( * ) ipiv, integer cmode, real, dimension( * ) c,
       integer info, real, dimension( * ) work, integer, dimension( * ) iwork)

SLA_GERCOND estimates the Skeel condition number for a general matrix.

🎯 Purpose 🎯

This is the original !> comment block, kept exactly as it is:

           !>
           !>    SLA_GERCOND estimates the Skeel condition number of op(A) * op2(C)
           !>    where op2 is determined by CMODE as follows
           !>    CMODE =  1    op2(C) = C
           !>    CMODE =  0    op2(C) = I
           !>    CMODE = -1    op2(C) = inv(C)
           !>    The Skeel condition number cond(A) = norminf( |inv(A)||A| )
           !>    is computed by computing scaling factors R such that
           !>    diag(R)*A*op2(C) is row equilibrated and computing the standard
           !>    infinity-norm condition number.
           !>

🌸 Parameters 🌸

• TRANS — TRANS is CHARACTER*1. Specifies the form of the system of equations:
  • = 'N': A * X = B (No transpose)
  • = 'T': A**T * X = B (Transpose)
  • = 'C': A**H * X = B (Conjugate Transpose = Transpose)
• N — N is INTEGER. The number of linear equations, i.e., the order of the matrix A. N >= 0.
• A — A is REAL array, dimension (LDA,N). On entry, the N-by-N matrix A.
• LDA — LDA is INTEGER. The leading dimension of the array A. LDA >= max(1,N).
• AF — AF is REAL array, dimension (LDAF,N). The factors L and U from the factorization A = P*L*U as computed by SGETRF.
• LDAF — LDAF is INTEGER. The leading dimension of the array AF. LDAF >= max(1,N).
• IPIV — IPIV is INTEGER array, dimension (N). The pivot indices from the factorization A = P*L*U as computed by SGETRF; row i of the matrix was interchanged with row IPIV(i).
• CMODE — CMODE is INTEGER. Determines op2(C) in the formula op(A) * op2(C) as follows:
  • CMODE = 1 → op2(C) = C
  • CMODE = 0 → op2(C) = I
  • CMODE = -1 → op2(C) = inv(C)
• C — C is REAL array, dimension (N). The vector C in the formula op(A) * op2(C).
• INFO — INFO is INTEGER:
  • = 0: Successful exit.
  • i > 0: The ith argument is invalid.
• WORK — WORK is REAL array, dimension (3*N). Workspace.
• IWORK — IWORK is INTEGER array, dimension (N). Workspace.2

Yes bestie, the source literally says Workspace.2 — I’m keeping it exactly like that. 💀

🫶 Author 🫶

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

Definition at line 148 of file sla_gercond.f.

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🦋 Author 🦋

Generated automatically by Doxygen for LAPACK from the source code.

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✨ cute sign-off time: the footer says LAPACK — Version 3.12.0 — /home/abui..._gercond.f(3). No date shown in this footer, bestie, just the version and page path. Bye! 💖🎀