Plot keeps coming up empty

Hi, I am trying to plot a graph, but my graph keeps coming up empty without any plots.

My code is below and I would appreciate it greatly if anyone could spot where I've gone wrong.

Thanks

hold on;

for i = 0:5

th = 0:pi/50:2*pi;

xv = i * cos(th); % for given value R

yv = i * sin(th); % R is the radius of the circle

rng default

xq = -1000:1000;

yq = -1000:1000;

[X,Y] = meshgrid(yq,xq);

[in,on] = inpolygon(X,Y,xv,yv);

Y = numel(X(in), Y(in))

E = abs(Y-pi*i^2)

plot(i, E)

grid on

end

hold off

[Rena Berman]

(Answers Dev) Restored Question.

Answer 1

[Walter Roberson]

plot(i, E, '*')

You are plotting one point at a time so you have no connecting lines. The default is no marker.

[Jenny Briggs]

Brilliant! Thank you so much!