ddeset

Create/alter delay differential equations (DDE) options structure

Syntax

• options = ddeset('name1',value1,'name2',value2,...)
  options = ddeset(oldopts,'name1',value1,...)
  options = ddeset(oldopts,newopts)
  ddeset
  

Description

options = ddeset('name1',value1,'name2',value2,...) creates an integrator options structure options in which the named properties have the specified values. Any unspecified properties have default values. It is sufficient to type only the leading characters that uniquely identify the property. Case is ignored for property names.

options = ddeset(oldopts,'name1',value1,...) alters an existing options structure oldopts.

options = ddeset(oldopts,newopts) combines an existing options structure oldopts with a new options structure newopts. Any new properties overwrite corresponding old properties.

ddeset with no input arguments displays all property names and their possible values.

DDE Properties

These properties are available:

Property	Value	Description
RelTol	Positive scalar {1e-3}	Relative error tolerance that applies to all components of the solution vector. The estimated error in each integration step satisfies |e(i)| <= max(RelTol*abs(y(i)),AbsTol(i)).
AbsTol	Positive scalar or vector {1e-6}	Absolute error tolerance that applies to all components of the solution vector. Elements of a vector of tolerances apply to corresponding components of the solution vector.
NormControl	on | {off}	Control error relative to norm of solution. Set this property on to request that dde23 control the error in each integration step with norm(e) <= max(RelTol*norm(y),AbsTol). By default dde23 uses a more stringent component-wise error control.
Stats	on | {off}	Display computational cost statistics.
Events	Function	The solver uses the specified function to locate where functions of t, y, Z vanish. See dde23 for details.
MaxStep	Positive scalar {0.1*tspan}	Upper bound on the magnitude of the step size. The default is one-tenth of the tspan interval.
InitialStep	Positive scalar	Suggested initial step size. The solver tries this first. By default the solver determines an initial step size automatically.
OutputFcn	Function	Installable output function. This output function is called by the solver after each time step. When a solver is called with no output arguments, OutputFcn defaults to the function odeplot. Otherwise, OutputFcn defaults to []. To create or modify an output function, see ODE Solver Output Properties in the "Differential Equations" section of the MATLAB documentation.
OutputSel	Vector of integers	Output selection indices. Specifies the components of the solution vector that dde23 passes to the OutputFcn. The default is all components.
Jumps	Vector	Location of discontinuities in solution. Points where the history or solution may have a jump discontinuity in a low-order derivative. See dde23 for details.
InitialY	Vector	Initial value of solution. By default the initial value of the solution is the value returned by history at the initial point. A different initial value can be supplied as the value of the InitialY property.