Why my plot doesn't show the line?

I'm very new with this program. Here is my code. Am I missing something? Could someone fix it and explain to me, thank you.

c = 3*10^8;
f0 = 10^9;
d0=10^3;
for i = 1:100
f1 = 1/(10*i/(c+10));
fd = f1-f0;
plot(i,fd)
hold on
end

Answer 1

[Star Strider]

If you must use a loop, you need to subscript ‘f1’:

f1(i) = 1/(10*i/(c+10));

However a loop is not necessary. Using element-wise operations, this works:

c = 3*10^8;
f0 = 10^9;
d0=10^3;

i = 1:100;
f1 = 1./(10*i/(c+10));
fd = f1-f0;
plot(i,fd)

See Array vs. Matrix Operations for details.

Answer 2

[Setsuna Yuuki.]

You can use this example:

i = linspace(0,100,1000);
c = 3*10^8;
f0 = 10^9;
d0=10^3;

f1 = 1./(10*i/(c+10));
fd = f0-f1;

plot(i,fd,'linewidth',2)
xlim([0 10])