SRC/sgebak.f(3)

okay bestie, welcome to SRC/sgebak.f(3) from the Library Functions Manual 💖 this one is giving “backward transformation but make it cute” energy, and yes, every detail is staying.

💖 NAME 💖

SRC/sgebak.f

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✨ SYNOPSIS ✨

🎀 Functions/Subroutines 🎀

subroutine sgebak (job, side, n, ilo, ihi, scale, m, v, ldv, info)
    SGEBAK

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🦋 Function/Subroutine Documentation 🦋

subroutine sgebak (character job, character side, integer n, integer ilo,
     integer ihi, real, dimension( * ) scale, integer m, real, dimension(
     ldv, * ) v, integer ldv, integer info)
    SGEBAK

🌸 Purpose 🌸

SGEBAK forms the right or left eigenvectors of a real general matrix by backward transformation on the computed eigenvectors of the balanced matrix output by SGEBAL. That’s the whole assignment, and it ate. 💅

🎀 Parameters 🎀

• JOB — CHARACTER*1; specifies the type of backward transformation required:
  • = 'N': do nothing, return immediately;
  • = 'P': do backward transformation for permutation only;
  • = 'S': do backward transformation for scaling only;
  • = 'B': do backward transformations for both permutation and scaling.
  • JOB must be the same as the argument JOB supplied to SGEBAL.
• SIDE — CHARACTER*1; tells you what’s in V:
  • = 'R': V contains right eigenvectors;
  • = 'L': V contains left eigenvectors.
• N — INTEGER; the number of rows of the matrix V. N >= 0. row count bestie, respect it.
• ILO — INTEGER.
• IHI — INTEGER; ILO and IHI are the integers determined by SGEBAL. 1 <= ILO <= IHI <= N, if N > 0; ILO=1 and IHI=0, if N=0.
• SCALE — REAL array, dimension (N); details of the permutation and scaling factors, as returned by SGEBAL. receipts from SGEBAL, literally.
• M — INTEGER; the number of columns of the matrix V. M >= 0. columns said hi.
• V — REAL array, dimension (LDV,M); on entry, the matrix of right or left eigenvectors to be transformed, as returned by SHSEIN or STREVC. On exit, V is overwritten by the transformed eigenvectors. glow-up happens in place, no cap.
• LDV — INTEGER; the leading dimension of the array V. LDV >= max(1,N).
• INFO — INTEGER; exit status tea ☕:
  • = 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.

Definition at line 128 of file sgebak.f.

🧚 Author 🧚

Generated automatically by Doxygen for LAPACK from the source code.

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okay bye bestie, this was SRC/sgebak.f(3) from LAPACK Version 3.12.0 💖✨