# How do I draw the graph of the same function several times?

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Delshad Ayoubi on 6 Oct 2017
Commented: Delshad Ayoubi on 6 Oct 2017
clear clc
x_t(1) = 0;
N = 10^2;
for t = 1:N
xlabel('t'), ylabel('x_t'), title('Random Walk')
a = sign(randn);
x_t(t+1) = x_t(t) + a;
plot(x_t,'b-')
hold on
pause(0.05);
end
How do I plot this same function several times? This is a random walk, every time it gets plotted I want it to look differently, which is exactly what sign(randn) does.
##### 2 CommentsShowHide 1 older comment
Delshad Ayoubi on 6 Oct 2017
Edited: Delshad Ayoubi on 6 Oct 2017
Yeah, and that is why every time it's plotted it looks different, random chance for +1/-1. I just want to know how to plot it several times while retaining them.

KSSV on 6 Oct 2017
M = 10 ;
N = 10^2;
x_t = zeros(M,N) ;
x_t(:,1) = rand ;
for i = 1:M
for t = 2:N
a = sign(randn);
x_t(i,t) = x_t(i,t-1) + a;
end
end
plot(x_t)
xlabel('t'), ylabel('x_t'), title('Random Walk')
It can be easily vectorised.
Delshad Ayoubi on 6 Oct 2017
I don't really understand that code very well. I'm new to programming. What is:
x_t(:,1) = rand;?
x_t = zeros(M,N);?
Seems very different compared with my code, isn't it possible to do a double loop or something with my and get the same results?