currents{ linear_solver{ } }

  • \(\mathrm{\textcolor{Aquamarine}{optional}}\)

  • items: \(\mathrm{maximum\;1}\)

This group allows modifying parameters impacting algorithm of linear equation solver in current equation.

Important

Maintained Keywords

The keywords below are available in at least one of currently published releases and are planned to be included also in the next release.

iterations

  • \(\mathrm{\textcolor{Aquamarine}{optional}}\)

  • type: \(\mathrm{integer}\)

  • unit: \(\mathrm{-}\)

  • values: \(\{1,2,3,4,\ldots\}\)

  • default: \(10000\)

Maximum number of iterations

abs_accuracy

  • \(\mathrm{\textcolor{Aquamarine}{optional}}\)

  • type: \(\mathrm{real\;number}\)

  • unit: \(\mathrm{-}\)

  • values: \([0.0, \ldots)\)

  • default: \(10^{-30}\)

rel_accuracy

  • \(\mathrm{\textcolor{Aquamarine}{optional}}\)

  • type: \(\mathrm{real\;number}\)

  • unit: \(\mathrm{-}\)

  • values: \([0.0, 10^{-2}]\)

  • default: \(10^{-13}\)

dkr_value

  • \(\mathrm{\textcolor{Aquamarine}{optional}}\)

  • type: \(\mathrm{real\;number}\)

  • unit: \(\mathrm{-}\)

  • values: \([0.0, 0.5]\)

  • default: \(11.0\)

A parameter to speed up calculations, affects preconditioning

Note

Negative values are ignored but will switch to a slightly slower but more stable preconditioning.

use_cscg

  • \(\mathrm{\textcolor{Aquamarine}{optional}}\)

  • type: \(\mathrm{choice}\)

  • choices: \(\mathrm{yes\;/\;no}\)

  • default: \(\mathrm{no}\)

Forces the slower but occasionally more robust CSCG (Composite Step Conjugate Gradient) linear solver to be used rather than the cg (Conjugate Gradient) linear solver. May occasionally prevent a diagonalization failure.

force_diagonal_preconditioner

  • \(\mathrm{\textcolor{Aquamarine}{optional}}\)

  • type: \(\mathrm{choice}\)

  • choices: \(\mathrm{yes\;/\;no}\)

  • default: \(\mathrm{no}\)

Only for debugging purposes, enabling will make code much slower or prevent convergence. Forces the use of a slower but more robust diagonal preconditioner.

This keyword should be used only for debugging purposes. Enabling the diagonal preconditioner makes algorithm much slower or prevent convergence. It can be enabled in case when then default preconditioning fails or the linear solver diverges. In such circumstances, also iterations may require further increasing.

force_iteration

  • \(\mathrm{\textcolor{Aquamarine}{optional}}\)

  • type: \(\mathrm{choice}\)

  • choices: \(\mathrm{yes\;/\;no}\)

  • default: \(\mathrm{no}\)

The keyword should be used only for debugging purposes. It will force iteration to reach maximum set by iterations regardless of whether the requested accuracy was reached or not.

extended_accuracy

  • \(\mathrm{\textcolor{Aquamarine}{optional}}\)

  • type: \(\mathrm{integer}\)

  • unit: \(\mathrm{-}\)

  • values: \(\{0,1\}\)

  • default: \(0\)

If set to 1, then current equation is solved using slower but more accurate solver. It is only implemented for not periodic 1D simulations.

Warning

This feature is at the prototyping stage and may not bring expected improvements.