How to make program for five realizations of ito process X = exp(t + 0.2W(t))

Question

I want to plot the following figures in octave.

I prepared the following program to plot one realization of ito process X =exp(t + 0.2W(t)) where W(t) is a Wiener process= $ \displaystyle\sum_{j=0}^{\pi-1}\sqrt{h}Z_j \sim N(0,\pi h) \sim N(0,t)$ where $\Delta{t}=h, t_{\pi h}= \pi h,Z_j \sim N(0,1) $

n=50;

t=linspace(0,1,n+1);

h=diff(t(1:2));

dw=sqrt(h)randn(n,1);

w=cumsum([0;dw]);

X=exp(t+0.2w);

plot(X)

But I got the below figure.

Plot(t,X)

What are the changes shall I require to make in the current program so that I get five realizations of ito process?

Answer 1

I am able to make program for five realizations of ito process X= exp(t+0.2*W(t)).

n=300; t=linspace(0,1,n+1)'; h=diff(t(1:2)); dw=sqrt(h)randn(n,5); w=cumsum([zeros(1,5);dw]); X=exp(t + 0.2w); plot(X)