Compute and plot Rayleigh Distribution probability density function

I am currently trying to plot the 90 and 50 percent fading ranges for three independent samples.Theh following code is for consecutive comvutions of pdf. I am able to get the cumative distribtion plot but I am having trouble converting it to the respective Rayleigh distribution pdf plot in order to find my upper and lower bound ranges. I know that the plot I need is the raylpdf function if I am not mistaken but I keep getting errors when I try to convert my plot. The code I am currently using is shown below: i am alsp attaching a pic of my current plot and the Rayleigh distribution pdf plot I am trying to convert it to.Thank you for your assistance.

N = 300;

a = 0;

b = 3;

delta = (b-a)/N;

x = linspace(a,b,N);

v = 2*x.*exp(-x.*x);

v1 = 18*x.*exp(-x.*x*9);

v2 = v1;

v3 = v1;

v4 = conv(v1,v2)*delta;

v1 = conv(v4,v3)*delta;

x = [0:3*N-3]*delta;

vcdf = cumsum(v1)*delta;

%plot(x(1:100),y,v,v1,'--');

plot(x,vcdf);

xlim([0,3]);

%legend('Rayleigh Distribution'. 'New Distribution');

xlabel('x (\sigma^(2)=0.5)');

title('(\bf Fig 2): cdf of New Distribution')

Answer 1

[VBBV]

plot(x,v1,'--',x(1:300),v);
axis([0 3 0 2])

Compare it with same vector lengths to view the Pdf

[Jose Iglesias]

It worked like a charm! Thank you so much!!