TSAlphaSetRadius#
sets the desired spectral radius of the method for TSALPHA (i.e. high-frequency numerical damping)
Synopsis#
#include "petscts.h"
PetscErrorCode TSAlphaSetRadius(TS ts, PetscReal radius)
Logically Collective
Input Parameters#
ts - timestepping context
radius - the desired spectral radius
Options Database Key#
-ts_alpha_radius
- set alpha 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:
\[
\begin{align*}
\alpha_m = 0.5*(3-\rho)/(1+\rho) \\
\alpha_f = 1/(1+\rho)
\end{align*}
\]
See Also#
TS: Scalable ODE and DAE Solvers, TS, TSALPHA, TSAlphaSetParams(), TSAlphaGetParams()
Level#
intermediate
Location#
Implementations#
TSAlphaSetRadius_Alpha() in src/ts/impls/implicit/alpha/alpha1.c
Index of all TS routines
Table of Contents for all manual pages
Index of all manual pages