TSAlpha2SetRadius#

sets the desired spectral radius of the method for TSALPHA2 (i.e. high-frequency numerical damping)

Synopsis#

#include "petscts.h"   
PetscErrorCode TSAlpha2SetRadius(TS ts, PetscReal radius)

Logically Collective

Input Parameters#

  • ts - timestepping context

  • radius - the desired spectral radius

Options Database Key#

  • -ts_alpha_radius - set the desired spectral radius

Notes#

The algorithmic parameters \(\alpha_m\) and \(\alpha_f\) of the generalized-\(\alpha\) method can be computed in terms of a specified spectral radius \(\rho\) in [0, 1] for infinite time step in order to control high-frequency numerical damping:

\[ \begin{align*} \alpha_m = (2-\rho)/(1+\rho) \\ \alpha_f = 1/(1+\rho) \end{align*} \]

See Also#

TS: Scalable ODE and DAE Solvers, TS, TSALPHA2, TSAlpha2SetParams(), TSAlpha2GetParams()

Level#

intermediate

Location#

src/ts/impls/implicit/alpha/alpha2.c

Implementations#

TSAlpha2SetRadius_Alpha() in src/ts/impls/implicit/alpha/alpha2.c


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Index of all manual pages