A Simple differential algebraic equation system

1 DAE example

This example shows how to write a simple DAE equation systems without any physical significance, with equations

containing formulas selected more or less at random, as in the class DAEexample below. The class contains two equations, one differential and one algebraic equation.

class DAEexample Real x(start = 0.9,fixed=true); Real y(fixed=false); equation der(y) + (1 + 0.5*sin(y))*der(x) = sin(time); x-y = exp(-0.9*x)*cos(y); end DAEexample;

2 Simulation of DAE example

Now we simulate the DAEexample in the interval from 0 to 1.

simulate( DAEexample, startTime=0, stopTime=1 )

Plot the results.

plot({x,y})

Plot of a simulation of a DAE (Differential Algebraic Equation) model.