lis_esolver_set_option(3)

🎀 NAME 🎀

lis_esolver_set_option — bestie, this is the one that sets the options for the eigensolver. That's it. That's the whole job. ✨

We're in the Lis Library Functions corner of the manual, and this page is lis_esolver_set_option(3), so pull up a chair, grab a strawberry 🍓, and let's go through every single flag together. No skipping, we're doing all of them.

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✨ SYNOPSIS ✨

#include "lis.h"

LIS_INT lis_esolver_set_option(char *text, LIS_ESOLVER *esolver);

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💖 DESCRIPTION 💖

You call this to set the options for the eigensolver. Like, all the knobs and dials, handed over as command line option text. That's the vibe. 💅

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📥 INPUT 📥

• text — the command line options. Yeah, the whole string of them.

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📤 OUTPUT 📤

• esolver — the eigensolver. It gets configured, and that's your result.

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🚪 EXIT STATUS 🚪

Here's what you can get back, no cap:

• 0 — the process is normally terminated. Everything ate. 💅
• unspecified — an error occurred. Not iconic. 😭

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📝 NOTE 📝

Okay so before we dive into the giant list, let's decode the notation, because it's giving shorthand:

The table below shows the available command line options, where -e {pi|1} means you can write -e pi or -e 1 (either one works, they're the same thing bestie), and -emaxiter [1000] indicates that -emaxiter defaults to 1,000.

So: curly braces = pick one of these, square brackets = that's the default. Got it? Good. 🫶

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👑 OPTIONS 👑

The following options are supported. Buckle up, it's a long list, but we're getting through all of it together. 🌈

• -e eigensolver — pick your eigensolver. The following options are supported for eigensolver:
  • -e {pi|1} — Power ⚡
  • -e {ii|2} — Inverse
    • -i [bicg] — the linear solver
  • -e {rqi|3} — Rayleigh Quotient
    • -i [bicg] — the linear solver
  • -e {cg|4} — CG
    • -i [cg] — the linear solver
  • -e {cr|5} — CR
    • -i [bicg] — the linear solver
  • -e {si|6} — Subspace
    • -ss [1] — the size of the subspace
  • -e {li|7} — Lanczos
    • -ss [1] — the size of the subspace
  • -e {ai|8} — Arnoldi
    • -ss [1] — the size of the subspace
  • -e {gpi|9} — Generalized Power
    • -i [bicg] — the linear solver
  • -e {gii|10} — Generalized Inverse
    • -i [bicg] — the linear solver
  • -e {grqi|11} — Generalized Rayleigh Quotient
    • -i [bicg] — the linear solver
  • -e {gcg|12} — Generalized CG
    • -i [cg] — the linear solver
  • -e {gcr|13} — Generalized CR
    • -i [bicg] — the linear solver
  • -e {gsi|14} — Generalized Subspace
    • -ss [1] — the size of the subspace
  • -e {gli|15} — Generalized Lanczos
    • -ss [1] — the size of the subspace
  • -e {gai|16} — Generalized Arnoldi
    • -ss [1] — the size of the subspace
• -i linear solver — now for the inner linear solver. The following options are supported for inner linear solver:
  • -i {cg|1} — CG
  • -i {bicg|2} — BiCG
  • -i {cgs|3} — CGS
  • -i {bicgstab|4} — BiCGSTAB
  • -i {bicgstabl|5} — BiCGSTAB(l)
    • -ell [2] — the degree l
  • -i {gpbicg|6} — GPBiCG
  • -i {tfqmr|7} — TFQMR
  • -i {orthomin|8} — Orthomin(m)
    • -restart [40] — the restart value m
  • -i {gmres|9} — GMRES(m)
    • -restart [40] — the restart value m
  • -i {jacobi|10} — Jacobi
  • -i {gs|11} — Gauss-Seidel
  • -i {sor|12} — SOR
    • -omega [1.9] — the relaxation coefficient omega, where 0<omega<2
  • -i {bicgsafe|13} — BiCGSafe
  • -i {cr|14} — CR
  • -i {bicr|15} — BiCR
  • -i {crs|16} — CRS
  • -i {bicrstab|17} — BiCRSTAB
  • -i {gpbicr|18} — GPBiCR
  • -i {bicrsafe|19} — BiCRSafe
  • -i {fgmres|20} — FGMRES(m)
    • -restart [40] — the restart value m
  • -i {idrs|21} — IDR(s)
    • -irestart [2] — the restart value s
  • -i {idr1|22} — IDR(1)
  • -i {minres|23} — MINRES
  • -i {cocg|24} — COCG
  • -i {cocr|25} — COCR
• -p preconditioner — and now the preconditioner. The following options are supported for preconditioner:
  • -p {none|0} — None
  • -p {jacobi|1} — Jacobi
  • -p {ilu|2} — ILU(k)
    • -ilu_fill [0] — the fill level k
  • -p {ssor|3} — SSOR
    • -ssor_omega [1.0] — the relaxation coefficient omega, where 0<omega<2
  • -p {hybrid|4} — Hybrid
    • -hybrid_i [sor] — the linear solver
    • -hybrid_maxiter [25] — the maximum number of iterations
    • -hybrid_tol [1.0e-3] — the convergence criterion
    • -hybrid_omega [1.5] — the relaxation coefficient omega of the SOR, where 0<omega<2
    • -hybrid_ell [2] — the degree l of the BiCGSTAB(l)
    • -hybrid_restart [40] — the restart values of the GMRES and Orthomin
  • -p {is|5} — I+S
    • -is_alpha [1.0] — the parameter alpha of I+alpha*S(m)
    • -is_m [3] — the parameter m of I+alpha*S(m)
  • -p {sainv|6} — SAINV
    • -sainv_drop [0.05] — the drop criterion
  • -p {saamg|7} — SA-AMG
    • -saamg_unsym [false] — select the unsymmetric version (the matrix structure must be symmetric)
    • -saamg_theta [0.05|0.12] — the drop criterion
  • -p {iluc|8} — Crout ILU
    • -iluc_drop [0.05] — the drop criterion
    • -iluc_rate [5.0] — the max fill-in ratio
  • -p {ilut|9} — ILUT
    • -ilut_drop [0.05] — the drop criterion
    • -ilut_rate [5.0] — the max fill-in ratio
• -adds true — Additive Schwarz
  • -adds_iter [1] — the number of iterations

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Other Options for eigensolver 🌸

• -emaxiter [1000] — the maximum number of iterations
• -etol [1.0e-12] — the convergence criterion
• -eprint [0] — the display of the residual
  • -eprint {none|0} — none
  • -eprint {mem|1} — save the residual history
  • -eprint {out|2} — display the residual history
  • -eprint {all|3} — save the residual history and display it on the screen
• -ie [ii] — the inner eigensolver used in Subspace, Lanczos, and Arnoldi
• -ige [ii] — the inner eigensolver used in Generalized Subspace, Generalized Lanczos, and Generalized Arnoldi
• -shift [0.0] — the amount of the shift
• -initx_ones [true] — the behavior of the initial vector x_0
  • -initx_ones {false|0} — given values
  • -initx_ones {true|1} — all values are set to 1
• -omp_num_threads [t] — the number of threads (t represents the maximum number of threads)
• -estorage [0] — the matrix storage format
• -estorage_block [2] — the block size of the BSR and BSC formats
• -ef [0] — the precision of the eigensolver
  • -ef {double|0} — double precision
  • -ef {quad|1} — double-double (quadruple) precision

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Other options for inner linear solver 🦋

• -maxiter [1000] — the maximum number of iterations
• -tol [1.0e-12] — the convergence criterion
• -print [0] — the display of the residual
  • -print {none|0} — none
  • -print {mem|1} — save the residual history
  • -print {out|2} — display the residual history
  • -print {all|3} — save the residual history and display it on the screen
• -scale [0] — the scaling
  • -scale {none|0} — no scaling
  • -scale {jacobi|1} — the Jacobi scaling
  • -scale {symm_diag|2} — the diagonal scaling
• -initx_zeros [true] — the behavior of the initial vector x_0
  • -initx_zero {false|0} — given values
  • -initx_zero {true|1} — all values are set to 0

bestie I'm just the messenger: the parent option is spelled -initx_zeros and the sub-options are spelled -initx_zero. That's literally what the page says, I'm not touching it. 💀

• -omp_num_threads [t] — the number of threads (t represents the maximum number of threads)
• -storage [0] — the matrix storage format
• -storage_block [2] — the block size of the BSR and BSC formats
• -f [0] — the precision of the linear solver
  • -f {double|0} — double precision
  • -f {quad|1} — double-double (quadruple) precision

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See Lis User Guide for full description. 📖

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👀 SEE ALSO 👀

• lis(3)
• http://www.ssisc.org/lis/

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okay that's the whole page, you made it, I'm so proud of you 🫶✨ this was the lis_esolver_set_option(3) man page from the Lis Library Functions set, dated 14 Sep 2017 — that's the version and the date right there, and yes it's giving vintage but she still serves. mwah, go configure an eigensolver bestie, you've got this 💅👑