TimeExplicit
Solve time-dependent problems with explicit time stepping.
Syntax
model.sol(sname).create(fname,"TimeExplicit")
model.sol(sname).feature(fname).set(pname,pvalue)
Description
 Operation feature. The TimeExplicit solver is used for solving time-dependent PDEs using the classic Runge-Kutta or the Adams-Bashforth 3 explicit time-stepping schemes
Table 6-73: Valid TimeExplicit Properties
Property
Values
Default
Description
algebraicsolveeverydt
positive double
0
Value of the period Δt, when algebraicsolvemethod is set to dt.
algebraicsolveeveryn
positive integer
1
Value of N, when algebraicsolvemethod is set to n.
algebraicsolvemethod
n | dt
n
Strategy used to solve the algebraic equations: every Nth step or periodically.
clist
String array
 
Provide values for constants as input parameters using a string array; for the corresponding constant names, use cname.
cname
String array
 
Provide names of constants as input parameters using a string array; for the corresponding constant values, use clist.
control
String
user
Name of the controlling study step or "user" if the feature is controlled manually.
endtimeinterpolation
Boolean
true
Interpolate the last time specified in the list of output times, if true. If set to false, the last output time is solved and not interpolated. In particular, the solver does not take steps past the last time.
erkorder
integer between 1 and 4
4
Runge-Kutta order.
exprs
String
 
Expression for time stepping when tstepping=elemexprs.
keeplog
on | off
off
Keep warnings in stored log.
linsolver
linear solver tag
 
Linear solver to use.
message
String
 
The log message from the last solution process.
odesolver
erk | ab3 | ab3loc
erk
Time explicit solver.
plot
on | off
off
Plot while solving.
plotfreq
tsteps | tout
tout
Times to update plot.
plotgroup
String
 
Name of plot group for plot while solving.
probefreq
tsteps | tout
tsteps
Times to update probe.
probes
vector of strings
 
Probed to use if probesel=manual.
probesel
all | none | manual
all
The probes to compute.
rktimestep
positive scalar
1e-3
Time step.
storeudot
on | off
on
Store time-derivatives.
tlist
vector of strings
 
Specified time list.
tout
tlist | tsteps | tstepsclosest
tlist
Times to store: output times by interpolation; every Nth step taken by solver; or steps taken by solver closest to output times.
tstepping
manual | elemexprs
manual
Manual or from expressions time stepping.
tstepsstore
positive integer
1
Value of N for every Nth step from the solver to store when tout is set to tsteps.
The order of the Runge-Kutta method can be set by the erkorder property. The size of the time step is controlled through the property rktimestep and can be given as a single scalar value, a (strictly monotone) numeric vector, or an expression using variables with global scope, which results in a scalar. For Adams-Bashforth 3 only a scalar constant value of the time step is allowed. Time stepping from expressions tstepping=elemexprs is useful for the Wave form PDE interface. A local time-stepping version of Adams-Bashforth 3 is available for the Wave Form PDE interface by odesolver = ab3loc.