View source for Van der Pol Oscillator binary variant(AMPL)

This page contains a discretized version of the MIOCP [[Van der Pol Oscillator (binary variant)]] in [http://www.ampl.org AMPL] format and with the package ampl_mintoc. You should be aware of the comments regarding discretization made on the [[:Category:AMPL|AMPL overview]] page. Note that you will need to include two generic [[support AMPL files]], mintocPre.mod and mintocPost.mod.

=== AMPL ===

The model in AMPL code for a fixed control discretization grid with a collocation method. We need a model file vanderpol.mod,
<source lang="AMPL">
# -------------------------------
# Model: van der Pol model, Mintoc.de, Clemens Zeile 2017
# Outer Convexification version
# -------------------------------



# Problem specific functions
# Note: scaled to  \in {0,1}
var f {k in X,o in 0..no,i in I} = (
	if      (k==1 && o==0) then x[2,i] 
	else if (k==2 && o==0) then -x[1,i]
	else if (k==2 && o==1) then -1*(1-(x[1,i])^2)*x[2,i]
	else if (k==2 && o==2) then 0.75*(1-(x[1,i])^2)*x[2,i]
	else if (k==2 && o==3) then -2*(1-(x[1,i])^2)*x[2,i]
	else 0
);

var lagrange{i in IC} = (x[1,i]^2+x[2,i]^2); #+w[1,i]^2


var re{k in RE} = (
	if           (k==1)   then x[1,0]  - 1
	else if      (k==2)   then x[2,0]  - 0
);



# -----------------------------------------
# Unused modeling parts


var mayer = 0;


var ri {k in RI} = (
	if      (k==1) then x[1,0]
);

var xa {k in XA, i in I} = (
	if      (k==1) then x[1,i]
);

var con {k in C, i in IC} = (
	if      (k==1) then x[1,i]
);

var vcon {k in VC, o in 0..no, i in IC} = (
	if      (k==1) then x[1,i]
);

var sw{o in Omega, i in IC diff {nt}, k in 1..nsw} = (
	if      (k==1) then x[1,i] - 0.8
	else if (k==2) then 1.4 - x[1,i]
);


</source>

the data file vanderpol.dat

<source lang="AMPL">
# -------------------------------
# Data: van der Pol model, Mintoc.de, Clemens Zeile 2017
# -------------------------------

# Dimensions, all other 0 by default
param nxd := 2;
param no := 3;
param nre := 2;
param nc := 0;


# Algorithmic parameters
param nt := 3600;
param ntperu := 2;

# Problem parameters

let T := 20;




# Initial values control
#let {i in IU} wi[1,i] := 0.9;
option randseed 10;
let {i in IU} wi[1,i] := Uniform01();

# Plot names
let nplots := 2;
let filename_base := "vanderpol";
let plotx[1] := 1;
let plotx[2] := 1;
let plotw[1] := 1;
for {k in 1..nxd} { let plotlambda[k] := 2; }


</source>


and the run file
<source lang="AMPL">
##############################
model ../mintocPre.mod;
model vanderpol.mod;
model ../mintocPost.mod;
data vanderpol.dat;
##############################

let isSOS1 := 1;
let integrator := "explicitEuler";




##############################
let integrator := "radau3";
let mode := "Relaxed";
include ../solve.run;
include ../plot1404.run;
include ../printOutput.run;

##############################
let mode := "CIA";
include ../solveMILP.run;
let mode := "Simulate";
include ../solve.run;
let filename_ext := "CIA";
include ../plot1404.run;
include ../printOutput.run;
</source>




[[Category:AMPL]]