ZGERFS(3)

💅 zgerfs(3) — Library Functions Manual 🦋

okay bestie, welcome to the zgerfs(3) page 💖 this is the Library Functions Manual energy, and the file we’re talking about is right here:

🎀 NAME 🎀

/home/abuild/rpmbuild/BUILD/lapack-static-3.12.0-build/lapack-3.12.0/SRC/zgerfs.f — yes, that whole path is the name, no cap 😭

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✨ SYNOPSIS ✨

🫶 Functions/Subroutines

       subroutine ZGERFS (trans, n, nrhs, a, lda, af, ldaf, ipiv, b, ldb, x,
           ldx, ferr, berr, work, rwork, info)
           ZGERFS

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💖 Function/Subroutine Documentation 💖

🧚 ZGERFS

   subroutine ZGERFS (character trans, integer n, integer nrhs, complex*16,
       dimension( lda, * ) a, integer lda, complex*16, dimension( ldaf, * ) af,
       integer ldaf, integer, dimension( * ) ipiv, complex*16, dimension( ldb,
       * ) b, integer ldb, complex*16, dimension( ldx, * ) x, integer ldx,
       double precision, dimension( * ) ferr, double precision, dimension( * )
       berr, complex*16, dimension( * ) work, double precision, dimension( * )
       rwork, integer info)
       ZGERFS

🌸 Purpose 🌸

ZGERFS is the glow-up subroutine for a computed solution to a system of linear equations 💅 it improves that solution and hands you back error bounds plus backward error estimates. Literally giving accuracy upgrade realness ✨

🎀 Parameters 🎀

• TRANS — is CHARACTER*1. It tells you which form of the system of equations we’re in:
  • = 'N': A * X = B (No transpose)
  • = 'T': A**T * X = B (Transpose)
  • = 'C': A**H * X = B (Conjugate transpose)
• N — is INTEGER. The order of the matrix A. N >= 0.
• NRHS — is INTEGER. The number of right hand sides, i.e., the number of columns of the matrices B and X. NRHS >= 0.
• A — is COMPLEX*16 array, dimension (LDA,N). The original N-by-N matrix A.
• LDA — is INTEGER. The leading dimension of the array A. LDA >= max(1,N).
• AF — is COMPLEX*16 array, dimension (LDAF,N). The factors L and U from the factorization A = P*L*U as computed by ZGETRF.
• LDAF — is INTEGER. The leading dimension of the array AF. LDAF >= max(1,N).
• IPIV — is INTEGER array, dimension (N). The pivot indices from ZGETRF; for 1<=i<=N, row i of the matrix was interchanged with row IPIV(i).
• B — is COMPLEX*16 array, dimension (LDB,NRHS). The right hand side matrix B.
• LDB — is INTEGER. The leading dimension of the array B. LDB >= max(1,N).
• X — is COMPLEX*16 array, dimension (LDX,NRHS). On entry, the solution matrix X, as computed by ZGETRS. On exit, the improved solution matrix X.
• LDX — is INTEGER. The leading dimension of the array X. LDX >= max(1,N).
• FERR — is DOUBLE PRECISION array, dimension (NRHS). The estimated forward error bound for each solution vector X(j) (the j-th column of the solution matrix X). If XTRUE is the true solution corresponding to X(j), FERR(j) is an estimated upper bound for the magnitude of the largest element in (X(j) - XTRUE) divided by the magnitude of the largest element in X(j). The estimate is as reliable as the estimate for RCOND, and is almost always a slight overestimate of the true error.
• BERR — is DOUBLE PRECISION array, dimension (NRHS). The componentwise relative backward error of each solution vector X(j) (i.e., the smallest relative change in any element of A or B that makes X(j) an exact solution).
• WORK — is COMPLEX*16 array, dimension (2*N).
• RWORK — is DOUBLE PRECISION array, dimension (N).
• INFO — is INTEGER.
  • = 0: successful exit
  • < 0: if INFO = -i, the i-th argument had an illegal value

💜 Internal Parameters 💜

• ITMAX is the maximum number of steps of iterative refinement.

👑 Author 👑

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

Definition at line 184 of file zgerfs.f.

🌟 Author 🌟

Generated automatically by Doxygen for LAPACK from the source code.

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and that’s the whole page, bestie 🫶 this one is LAPACK, Version 3.12.0, source footer says /home/abui...RC/zgerfs.f(3) — no date line on the page, so no fake date energy from me 💀🎀