# trapezoidal_fixed

trapezoidal_fixed, a MATLAB code which solves one or more ordinary differential equations (ODE) using the (implicit) trapezoidal method, using a fixed-point method to handle the implicit system.

Unless the right hand side of the ODE is linear in the dependent variable, each trapezoidal step requires the solution of an implicit nonlinear equation. Such equations can be approximately solved using methods such as fixed point iteration, or an implicit equation solver like fsolve().

### Languages:

trapezoidal_fixed is available in a MATLAB version and an Octave version and a Python version and an R version.

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### Source Code:

• trapezoidal_fixed.m, a version of the trapezoidal method that solves the implicit trapezoidal step equation using a fixed point iteration.

Last revised on 26 April 2021.