Why I am not getting anything from the plot?

The plot is supposed to be two waves x1_rec and x2_rec. But I am not getting anything from the code. Can anyone please elaborate why?

clear all; close all; clc;
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%                       Simulation                          %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%value of constants
a1=0.1;a2=0.2;
omega1=5;omega2=4;
G=1;C12=0.01;C21=0.02;
dt=0.01;   %step size
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
x1(1)=0.5;
y1(1)=0.5;
x2(1)=1;
y2(1)=1;
for i=2:1000
    x1(i)=x1(i-1)+((a1-x1(i-1)^2-y1(i-1)^2)*x1(i-1)-omega1*y1(i-1)+G*C12*(x2(i-1)-x1(i-1)))*dt;
    y1(i)=y1(i-1)+((a1-x1(i-1)^2-y1(i-1)^2)*y1(i-1)+omega1*x1(i-1)+G*C12*(y2(i-1)-y1(i-1)))*dt;
    x2(i)=x2(i-1)+((a2-x2(i-1)^2-y2(i-1)^2)*x2(i-1)-omega2*y2(i-1)+G*C21*(x1(i-1)-x2(i-1)))*dt;
    y2(i)=y2(i-1)+((a2-x2(i-1)^2-y2(i-1)^2)*y2(i-1)+omega2*x2(i-1)+G*C21*(y1(i-1)-y2(i-1)))*dt;
end
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%                       Observation                        %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
    N_measurements=31;
    N_basis=31;
    index=randi([100,999],1,N_measurements);
    Xdot1=zeros([1,N_measurements]);
    Ydot1=zeros([1,N_measurements]);
    Xdot2=zeros([1,N_measurements]);
    Ydot2=zeros([1,N_measurements]);
    for ni=1:N_measurements
        Xdot1(ni)=(x1(index(ni)+1)-x1(index(ni)))/dt;
        Ydot1(ni)=(y1(index(ni)+1)-y1(index(ni)))/dt;
        Xdot2(ni)=(x2(index(ni)+1)-x2(index(ni)))/dt;
        Ydot2(ni)=(y2(index(ni)+1)-y2(index(ni)))/dt;
    end
    M=zeros([N_measurements,N_basis]);
    for i=1:N_measurements
        for j=1:N_basis 
            if j==1
               M(i,j)=1;
            elseif j==2
               M(i,j)=x1(index(i));
            elseif j==3
               M(i,j)=y1(index(i));
            elseif j==4
               M(i,j)=x2(index(i));
            elseif j==5
               M(i,j)=y2(index(i));
            elseif j==6
               M(i,j)=x1(index(i))^2;
            elseif j==7
                M(i,j)=x2(index(i))^2;
            elseif j==8
                M(i,j)=y1(index(i))^2;
            elseif j==9
                M(i,j)=y2(index(i))^2;
            elseif j==10
                M(i,j)=x1(index(i))*x2(index(i));
            elseif j==11
                M(i,j)=x1(index(i))*y1(index(i));   
            elseif j==12
                M(i,j)=x1(index(i))*y2(index(i));  
            elseif j==13
                M(i,j)=x2(index(i))*y1(index(i));  
            elseif j==14
                M(i,j)=x2(index(i))*y2(index(i)); 
            elseif j==15
                M(i,j)=y1(index(i))*y2(index(i)); 
            elseif j==16
                M(i,j)=x1(index(i))^3;  
            elseif j==17
                M(i,j)=y1(index(i))^3;
            elseif j==18
                M(i,j)=x2(index(i))^3; 
            elseif j==19
                M(i,j)=y2(index(i))^3; 
            elseif j==20
                M(i,j)=x1(index(i))^2*x2(index(i));
            elseif j==21
                M(i,j)=x1(index(i))^2*y1(index(i));
            elseif j==22
                M(i,j)=x1(index(i))^2*y2(index(i));
            elseif j==23
                M(i,j)=x2(index(i))^2*x1(index(i));
            elseif j==24
                M(i,j)=x2(index(i))^2*y1(index(i));
            elseif j==25
                M(i,j)=x2(index(i))^2*y2(index(i));
            elseif j==26
                M(i,j)=y1(index(i))^2*x1(index(i));
            elseif j==27
                M(i,j)=y1(index(i))^2*x2(index(i));
            elseif j==28
                M(i,j)=y1(index(i))^2*y2(index(i));
            elseif j==29
                M(i,j)=y2(index(i))^2*x1(index(i));
            elseif j==30
                M(i,j)=y2(index(i))^2*x2(index(i));
            else j==31   
                M(i,j)=y2(index(i))^2*y1(index(i));
            end
        end
    end
    %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
    %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
    %                       RIP                      %
    %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
    Norms=zeros([1,N_basis]);
    for j=1:N_basis
        Norms(j)=norm(M(:,j));
    end
    for i=1:N_measurements
        for j=1:N_basis
            M(i,j)=M(i,j)/Norms(j);
        end
    end
  %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
x1_rec(1)= x1(1);
x2_rec(1)= x2(1);
y1_rec(2)= y1(1);
y2_rec(2)= y2(1);
a1=0.0000;
a2=0.0900;
a3=-5.0000;
a4=0.0100;
a5=0.0000;
a6=0.0000;
a7=0.0000;
a8=0.0000;
a9=0.0000;
a10=0.0000;
a11=0.0000;
a12=0.0000;
a13=0.0000;
a14=0.0000;
a15=0.0000;
a16=-1.0000;
a17=0.0000;
a18=0.0000;
a19=0.0000;
a20=0.0000;
a21=0.0000;
a22=0.0000;
a23=0.0000;
a24=0.0000;
a25=0.0000;
a26=-1.0000;
a27=0.0000;
a28=0.0000;
a29=0.0000;
a30=0.0000;
a31=0.0000;
%b=y1
b1=0.0000;
b2=5.0000;
b3=0.0900;
b4=0.0000;
b5=0.0100;
b6=0.0000;
b7=0.0000;
b8=0.0000;
b9=0.0000;
b10=0.0000;
b11=0.0000;
b12=0.0000;
b13=0.0000;
b14=0.0000;
b15=0.0000;
b16=0.0000;
b17=-1.0000;
b18=0.0000;
b19=0.0000;
b20=0.0000;
b21=-1.0000;
b22=0.0000;
b23=0.0000;
b24=0.0000;
b25=0.0000;
b26=0.0000;
b27=0.0000;
b28=0.0000;
b29=0.0000;
b30=0.0000;
b31=0.0000;
%c=x2
c1=0.0000;
c2=0.0200;
c3=0.0000;
c4=0.1800;
c5=-4.0000;
c6=0.0000;
c7=0.0000;
c8=0.0000;
c9=0.0000;
c10=0.0000;
c11=0.0000;
c12=0.0000;
c13=0.0000;
c14=0.0000;
c15=0.0000;
c16=0.0000;
c17=0.0000;
c18=-1.0000;
c19=0.0000;
c20=0.0000;
c21=0.0000;
c22=0.0000;
c23=0.0000;
c24=0.0000;
c25=0.0000;
c26=0.0000;
c27=0.0000;
c28=0.0000;
c29=0.0000;
c30=-1.0000;
c31=0.0000; 
%d=y2
d1=0.0000;
d2=0.0000;
d3=0.0200;
d4=4.0000;
d5=0.1800;
d6=0.0000;
d7=0.0000;
d8=0.0000;
d9=0.0000;
d10=0.0000;
d11=0.0000;
d12=0.0000;
d13=0.0000;
d14=0.0000;
d15=0.0000;
d16=0.0000;
d17=0.0000;
d18=0.0000;
d19=-1.0000;
d20=0.0000;
d21=0.0000;
d22=0.0000;
d23=0.0000;
d24=0.0000;
d25=-1.0000;
d26=0.0000;
d27=0.0000;
d28=0.0000;
d29=0.0000;
d30=0.0000;
d31=0.0000;
for i=2:32
y1_rec(i)= b1+b2*x1_rec(i-1)+b3*y1_rec(i-1)+b4*x2_rec(i-1)+b5*y2_rec(i-1)+b6*x1_rec(i-1)^2+b7*x2_rec(i-1)^2+b8*y1_rec(i-1)^2+b9*y2_rec(i-1)^2+b10*x1_rec(i-1)*x2_rec(i-1)+b11*x1_rec(i-1)*y1_rec(i-1)+b12*x1_rec(i-1)*y2_rec(i-1)+b13*x2_rec(i-1)*y1_rec(i-1)+b14*x2_rec(i-1)*y2_rec(i-1)+b15*y1_rec(i-1)*y2_rec(i-1)+b16*x1_rec(i-1)^3+b17*y1_rec(i-1)^3+b18*x2_rec(i-1)^3+b19*y2_rec(i-1)^3+b20*x1_rec(i-1)^2*x2_rec(i-1)+b21*x1_rec(i-1)^2*y1_rec(i-1)+b22*x1_rec(i-1)^2*y2_rec(i-1)+b23*x2_rec(i-1)^2*x1_rec(i-1)+b24*x2_rec(i-1)^2*y1_rec(i-1)+b25*x2_rec(i-1)^2*y2_rec(i-1)+b26*y1_rec(i-1)^2*x1_rec(i-1)+b27*y1_rec(i-1)^2*x2_rec(i-1)+b28*y1_rec(i-1)^2*y2_rec(i-1)+b29*y2_rec(i-1)^2*x1_rec(i-1)+b30*y2_rec(i-1)^2*x2_rec(i-1)+b31*y2_rec(i-1)^2*y1_rec(i-1);
y2_rec(i)= d1+d2*x1_rec(i-1)+d3*y1_rec(i-1)+d4*x2_rec(i-1)+d5*y2_rec(i-1)+d6*x1_rec(i-1)^2+d7*x2_rec(i-1)^2+d8*y1_rec(i-1)^2+d9*y2_rec(i-1)^2+d10*x1_rec(i-1)*x2_rec(i-1)+d11*x1_rec(i-1)*y1_rec(i-1)+d12*x1_rec(i-1)*y2_rec(i-1)+d13*x2_rec(i-1)*y1_rec(i-1)+d14*x2_rec(i-1)*y2_rec(i-1)+d15*y1_rec(i-1)*y2_rec(i-1)+d16*x1_rec(i-1)^3+d17*y1_rec(i-1)^3+d18*x2_rec(i-1)^3+d19*y2_rec(i-1)^3+d20*x1_rec(i-1)^2*x2_rec(i-1)+d21*x1_rec(i-1)^2*y1_rec(i-1)+d22*x1_rec(i-1)^2*y2_rec(i-1)+d23*x2_rec(i-1)^2*x1_rec(i-1)+d24*x2_rec(i-1)^2*y1_rec(i-1)+d25*x2_rec(i-1)^2*y2_rec(i-1)+d26*y1_rec(i-1)^2*x1_rec(i-1)+d27*y1_rec(i-1)^2*x2_rec(i-1)+d28*y1_rec(i-1)^2*y2_rec(i-1)+d29*y2_rec(i-1)^2*x1_rec(i-1)+d30*y2_rec(i-1)^2*x2_rec(i-1)+d31*y2_rec(i-1)^2*y1_rec(i-1);
x1_rec(i)= a1+a2*x1_rec(i-1)+a3*y1_rec(i-1)+a4*x2_rec(i-1)+a5*y2_rec(i-1)+a6*x1_rec(i-1)^2+a7*x2_rec(i-1)^2+a8*y1_rec(i-1)^2+a9*y2_rec(i-1)^2+a10*x1_rec(i-1)*x2_rec(i-1)+a11*x1_rec(i-1)*y1_rec(i-1)+a12*x1_rec(i-1)*y2_rec(i-1)+a13*x2_rec(i-1)*y1_rec(i-1)+a14*x2_rec(i-1)*y2_rec(i-1)+a15*y1_rec(i-1)*y2_rec(i-1)+a16*x1_rec(i-1)^3+a17*y1_rec(i-1)^3+a18*x2_rec(i-1)^3+a19*y2_rec(i-1)^3+a20*x1_rec(i-1)^2*x2_rec(i-1)+a21*x1_rec(i-1)^2*y1_rec(i-1)+a22*x1_rec(i-1)^2*y2_rec(i-1)+a23*x2_rec(i-1)^2*x1_rec(i-1)+a24*x2_rec(i-1)^2*y1_rec(i-1)+a25*x2_rec(i-1)^2*y2_rec(i-1)+a26*y1_rec(i-1)^2*x1_rec(i-1)+a27*y1_rec(i-1)^2*x2_rec(i-1)+a28*y1_rec(i-1)^2*y2_rec(i-1)+a29*y2_rec(i-1)^2*x1_rec(i-1)+a30*y2_rec(i-1)^2*x2_rec(i-1)+a31*y2_rec(i-1)^2*y1_rec(i-1);
x2_rec(i)= c1+c2*x1_rec(i-1)+c3*y1_rec(i-1)+c4*x2_rec(i-1)+c5*y2_rec(i-1)+c6*x1_rec(i-1)^2+c7*x2_rec(i-1)^2+c8*y1_rec(i-1)^2+c9*y2_rec(i-1)^2+c10*x1_rec(i-1)*x2_rec(i-1)+c11*x1_rec(i-1)*y1_rec(i-1)+c12*x1_rec(i-1)*y2_rec(i-1)+c13*x2_rec(i-1)*y1_rec(i-1)+c14*x2_rec(i-1)*y2_rec(i-1)+c15*y1_rec(i-1)*y2_rec(i-1)+c16*x1_rec(i-1)^3+c17*y1_rec(i-1)^3+c18*x2_rec(i-1)^3+c19*y2_rec(i-1)^3+c20*x1_rec(i-1)^2*x2_rec(i-1)+c21*x1_rec(i-1)^2*y1_rec(i-1)+c22*x1_rec(i-1)^2*y2_rec(i-1)+c23*x2_rec(i-1)^2*x1_rec(i-1)+c24*x2_rec(i-1)^2*y1_rec(i-1)+c25*x2_rec(i-1)^2*y2_rec(i-1)+c26*y1_rec(i-1)^2*x1_rec(i-1)+c27*y1_rec(i-1)^2*x2_rec(i-1)+c28*y1_rec(i-1)^2*y2_rec(i-1)+c29*y2_rec(i-1)^2*x1_rec(i-1)+c30*y2_rec(i-1)^2*x2_rec(i-1)+c31*y2_rec(i-1)^2*y1_rec(i-1);
end
    figure
    hold on
    plot(x1_rec,'Y')
    plot(x2_rec,'b')

[Cris LaPierre]

Are you not getting anything, or not getting what you expected? When I run it, I get the following plot (Note that yellow is really hard to see).

[Image Analyst]

Do you mean "waves" like a oscillating wave like sin or cos, or "waveforms" like some arbitrary signal like the one Cris says your code produces?

Why do you say "I am not getting anything" when it clearly DOES produce a plot?

[Louka Fortin-Sirianni]

But they WOULDN'T spend time getting on HERE to ask the QUESTION, right? So IT doesn't WORK on THEIR side, right?

[Rik]

Without a clear description of what 'not working' means, we tend to assume the code will result in an error or an empty plot. Neither is the case here. So either it does work, or the OP should describe what is actually the problem.

With such a large number of numbered variables it is not hard to imagine there is a typo somewhere in there resulting in an unexpected shape of the graph. The first line of code is also a 'code smell'.

[Heya :)]

The waves should be like this but I am getting the straight lines.