# Plotting data from for loop

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Alec Carruthers on 4 Apr 2017
Commented: KSSV on 5 Apr 2017
Here is my code:
T=290;
R=287;
G=1.4;
Cv= R/(G-1);
e=Cv*T;
V= (0:1:1000);
Ke= .5*(V.^2);
for i = 1:1:length(V)
Ratio(i)= Ke(i)/e;
plot(Ratio);
hold on
end
Basically I want to plot "Ratio" with all of the stored Ke values on the graph. When I run the code, it gives me a thousand sets of a thousand entries instead of just 1 set with a thousand entries. All of the sets are the same, I just don't know why it is producing that many sets.

KSSV on 4 Apr 2017
It is because, you are plotting Ratio inside the loop and you have not mentioned the X data. You can plot Ratio outside the loop.
T=290;
R=287;
G=1.4;
Cv= R/(G-1);
e=Cv*T;
V= (0:1:1000);
Ke= .5*(V.^2);
Ratio = zeros(size(V)) ;
for i = 1:1:length(V)
Ratio(i)= Ke(i)/e;
end
plot(Ratio);
It can be vectorised without loop as below:
% Vector
Ratio = Ke/e ;

Alec Carruthers on 4 Apr 2017
Thank you for the help. Your code gives me the same data, but it is only one set instead of a thousand.
KSSV on 5 Apr 2017
How it can be thousand?