Sindy example not working in MATLAB

[jasonnicholson]

The Sindy example in MATLAB is not working.

I modified the code of the example only slightly so that some indexing issues don't stop MATLAB. Instead, we end up erroring out at line 159. See stack trace below. The code completes in Octave.

clc; clear; close all;


% Load CSV data
X = csvread('..\data\MotorRotation.csv'); % Can be found in the folder "data"
t = X(:, 1);
u = X(:, 2);
y = X(:, 3);
sampleTime = 0.02;

% Do filtering of y
y = filtfilt2(y', t', 0.1)';

% Sindy - Sparce identification Dynamics
activations = [1 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0]; % Enable or disable the candidate functions such as sin(u), x^2, sqrt(y) etc...
lambda = 0.05;
l = length(u);
h = floor(l/2);
s = ceil(l/2);
fx_up = sindy(u(1:h), y(1:h), activations, lambda, sampleTime); % We go up
fx_down = sindy(u(s:end), y(s:end), activations, lambda, sampleTime); % We go down

% Simulation up
x0 = y(1);
u_up = u(1:h);
u_up = u_up(1:100:end)';
stepTime = 1.2;
[x_up, t] = nlsim(fx_up, u_up, x0, stepTime, 'ode15s');

% Simulation down 
x0 = y(s);
u_down = u(s:end)
u_down = u_down(1:100:end)';
stepTime = 1.2;
[x_down, t] = nlsim(fx_down, u_down, x0, stepTime, 'ode15s');

% Compare 
figure
plot([x_up x_down])
hold on 
plot(y(1:100:end));
legend('Simulation', 'Measurement')
ylabel('Rotation')
xlabel('Time')
grid on

[swadexi]

I Fixed it By change line 133 used_labels = [""]; to used_labels = []; in /sourcecode/sindy.m

[DanielMartensson]

I will update sindy.m file so it much easier to use. I have plans that it should only focusing on polynomial regression because I find it very useful and I have tried it out with hydraulical systems and it works like a charm.

[jasonnicholson]

@DanielMartensson, have you fixed this?

[DanielMartensson]

@DanielMartensson, have you fixed this?

@jasonnicholson I have tried the example. It seems to work for me.

[jasonnicholson]

It works in Octave but not MATLAB. Something is different.

[DanielMartensson]

Try it now. I have changed sindy.m a lot.