GeezerVison is showing octave.sourceforge.io — Function Reference: odeset
- : odestruct = odeset ()
- : odestruct = odeset ("field1", value1, "field2", value2, …)
- : odestruct = odeset (oldstruct, "field1", value1, "field2", value2, …)
- : odestruct = odeset (oldstruct, newstruct)
- : odeset ()
-
Create or modify an ODE options structure.
When called with no input argument and one output argument, return a new ODE
options structure that contains all possible fields initialized to their
default values. If no output argument is requested, display a list of
the common ODE solver options along with their default value.
If called with name-value input argument pairs "field1",
"value1", "field2", "value2", … return a new
ODE options structure with all the most common option fields
initialized, and set the values of the fields "field1",
"field2", … to the values value1, value2,
….
If called with an input structure oldstruct then overwrite the
values of the options "field1", "field2", … with
new values value1, value2, … and return the
modified structure.
When called with two input ODE options structures oldstruct and
newstruct overwrite all values from the structure
oldstruct with new values from the structure newstruct.
Empty values in newstruct will not overwrite values in
oldstruct.
The most commonly used ODE options, which are always assigned a value
by odeset, are the following:
- AbsTol
Absolute error tolerance.
- BDF
Use BDF formulas in implicit multistep methods.
Note: This option is not yet implemented.
- Events
Event function. An event function must have the form
[value, isterminal, direction] = my_events_f (t, y)
- InitialSlope
Consistent initial slope vector for DAE solvers.
- InitialStep
Initial time step size.
- Jacobian
Jacobian matrix, specified as a constant matrix or a function of
time and state.
- JConstant
Specify whether the Jacobian is a constant matrix or depends on the
state.
- JPattern
If the Jacobian matrix is sparse and non-constant but maintains a
constant sparsity pattern, specify the sparsity pattern.
- Mass
Mass matrix, specified as a constant matrix or a function of
time and state.
- MassSingular
Specify whether the mass matrix is singular. Accepted values include
"yes", "no", "maybe".
- MaxOrder
Maximum order of formula.
- MaxStep
Maximum time step value.
- MStateDependence
Specify whether the mass matrix depends on the state or only on time.
- MvPattern
If the mass matrix is sparse and non-constant but maintains a
constant sparsity pattern, specify the sparsity pattern.
Note: This option is not yet implemented.
- NonNegative
Specify elements of the state vector that are expected to remain
nonnegative during the simulation.
- NormControl
Control error relative to the 2-norm of the solution, rather than its
absolute value.
- OutputFcn
Function to monitor the state during the simulation. For the form of
the function to use see odeplot.
- OutputSel
Indices of elements of the state vector to be passed to the output
monitoring function.
- Refine
Specify whether output should be returned only at the end of each
time step or also at intermediate time instances. The value should be
a scalar indicating the number of equally spaced time points to use
within each timestep at which to return output.
Note: This option is not yet implemented.
- RelTol
Relative error tolerance.
- Stats
Print solver statistics after simulation.
- Vectorized
Specify whether odefun can be passed multiple values of the
state at once.
Field names that are not in the above list are also accepted and
added to the result structure.
See also: odeget.
Demonstration 1
The following code
## A new ODE options structure with default values is created.
odeoptA = odeset ();
gives an example of how 'odeset' is used.
Demonstration 2
The following code
## A new ODE options structure with manually set options
## for "AbsTol" and "RelTol" is created.
odeoptB = odeset ("AbsTol", 1e-2, "RelTol", 1e-1);
gives an example of how 'odeset' is used.
Demonstration 3
The following code
## A new ODE options structure is created from odeoptB with
## a modified value for option "NormControl".
odeoptB = odeset ("AbsTol", 1e-2, "RelTol", 1e-1);
odeoptC = odeset (odeoptB, "NormControl", "on");
gives an example of how 'odeset' is used.
Package: octave
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