// test_filter2nd.thd
// demonstrates the use of a second order filter model
// 

// include models we need
#include "genstep.thd"
#include "filter2nd.thd"

// set up model
var AMP = 1;
var gen = GenStep(AMP , .1 ); // step generator with amplitude AMP, start at .1
 
var filter  = Filter2nd  (gen.m_state ,  20, .4); // Filter gen signal with freq = 20, damping = .1

 // set up diagram
var g = Graph("Filter");

// helper functions for plotting the diagram
function f_gen()
{
	return gen .m_state.value;
};
function f_filter()
{
	return  filter .m_state .value;
};

g.addSeries(f_gen,    -AMP ,AMP ,RGB(0,128,0), GRAPH_MIN_Y|GRAPH_MAX_Y, "gen");
g.addSeries(f_filter, -AMP ,AMP ,RGB(255,0,0), GRAPH_MIN_Y|GRAPH_MAX_Y, "filter2nd");

// simulate

while (simulator.time < 1)
{
	simulator.run(.01);   
};