`ode23t`

Trapezoidal-rule solver for moderately stiff equations and differential-algebraic systems.

Category: Mathematics > Numerical Integration and Differential Equations

Syntax

[t, y] = ode23t(odefun, tspan, y0)

Integrates y' = odefun(t, y).

[t, y] = ode23t(odefun, tspan, y0, options)

Also applies options from odeset, including a 'Mass' matrix.

Description

The implicit trapezoidal rule, with a free interpolant, does not damp oscillations, which makes ode23t the stiff solver to prefer when the solution is oscillatory and you want to keep its amplitude. It accepts a singular mass matrix, so it also solves index-1 differential-algebraic equations.

For strong damping of stiff transients, ode15s or ode23tb are better.

Input arguments

odefun: Handle dydt = odefun(t, y).
tspan: [t0 tf] or a vector of output times.
y0: Vector of initial values.

Output arguments

t, y: Time points and solution, laid out as for ode45.

Example

Decay toward a cosine

f = @(t, y) -50*(y - cos(t));
[t, y] = ode23t(f, [0 1], 0);
fprintf('%.3f\n', y(end))

Output

0.557

ode23t