MATLAB: How to output all these row vectors into a matrix

functionmatrixoutputplot

Hello, I am almost finished with an assignment for the course Linear Algebra but I am stuck with the very last part of this one question. We had to create a loop inside a function that would result in (for my case) 225 iterations and thus 225 vectors x in R2. Now we have to transpose these column vectors x into row vectors and make a matrix X that consists of 225 rows with each row being a row vector x. Eventually, we have to plot this matrix with the first column on the x axis and the second column on the y axis. My question is, how to get this output matrix? I have been looking over the internet but every situation seems to differ from mine and can't figure it out. Thank you very much in advance! This is what I already have:
function X=Exercise4(v);
v(1)=2; v(2)=0; v(3)=1; v(4)=4; v(5)=2; v(6)=8; v(7)=0;
v=[v(1);v(2);v(3);v(4);v(5);v(6);v(7)];
%Fill in and create all the matrices given
S=[1,v(4)/5;0,1];
a=pi*(v(2)+12)/300;
R=[cos(a),-sin(a);sin(a),cos(a)];
r=0.97;
A=r*S*R*(S^-1);
iter=0; 
x=[v(5)+1;v(6)]; %This is the first value of x (x(0)) that was given in the question
MaxNorm=0.01; %The length of the vector could not be smaller than 0.01
while norm(x)>=MaxNorm 
    x=A*x
    iter=iter+1 %Count the number of iterations
end
disp('Iterations'); %Display the number of iterations
disp(iter);

Best Answer

You just need to store your x values inside the loop in an array. Anyway, firstly when you write
v(1)=2; v(2)=0; v(3)=1; v(4)=4; v(5)=2; v(6)=8; v(7)=0;
you are already creating a vector so you don't need the line that follows. Or you could simply write
v = [2 0 1 4 2 8 0];
Both mean the same thing.
Nextly, you could save the given values like,
x_init=[v(5)+1;v(6)]; %This is the first value of x (x(0)) that was given in the question
MaxNorm=0.01; %The length of the vector could not be smaller than 0.01
and then define iter as 1 to calculate the first iteration outside the loop like,
iter=1; 
x(:,iter) = A*x_init;
and then go inside the loop to calculate the remaining iterations until the condition is satisfied,
while norm(x(:,iter))>=MaxNorm
    iter=iter+1; %Count the number of iterations
    x(:,iter)=A*x(:,iter-1);
end
finally, transpose the matrix using,
x = x.';
then plot or do whatever you want to do with it,
plot(x)
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