Question on Chebyshev filter

Question

What does the output signal look like when you insert $2000 Hz$ square pulses to chebyshev filter with parameters: (Matlab syntax). I tried to do it like this but I don't understand where it goes wrong.

%Making the square pulses

Fs = 1000000;
t = [0:1/Fs:50e-4]; 
f = 2000;

%square pulse with 50% duty cycle

xt = 1*square(2*pi*f*t, 50);

%Making the filter

Wp = [1000 3000]; 
Ws = [100 3900]; 
[n,Wn] = cheb1ord(Wp,Ws,3,20,'s');
[b,a] = cheby1(n,3,Wn,'s');



%Filtering with the coefficient 

xt_filtered = filter(b,a,xt);

%Plotting the filtered signal

plot(t,xt_filtered);

But I get something like this which doesn't make sense..?

Answer 1

Allowing for differences between Matlab and Octave ( I only have Gnu Octave to play with,) and correcting the errors noted in the comments, I get the following: Needed fixes:

1. Values for Wp and Ws divided by half of sampling rate - the cheb1ord function requires frequencies be given relative to the Nyquist frequency.
2. Removed 's' (not allowed for Octave anyway.)

To make the code work for Octave, I had to make the following changes:

1. Remove duty cycle value from square
2. Remove 's' from cheb1ord and cheby1

Code for Octave (should run under Matlab as well:)

%Making the square pulses
Fs = 1000000;
nyq=Fs/2;
t = 0:1/Fs:50e-4; 
f = 2000;

%square pulse with 50% duty cycle
xt = square(2*pi*f*t);

%Making the filter
Wp = [1000/nyq 3000/nyq]; 
Ws = [100/nyq 3900/nyq];
[n,Wn] = cheb1ord(Wp,Ws,3,20);
[b,a] = cheby1(n,3,Wn,'s');

%Filtering with the coefficients 
xt_filtered = filter(b,a,xt);

%Plotting the filtered signal
subplot (211);
plot(t,xt);
subplot(212);
plot(t,xt_filtered);