# HELP! My for loop code won't produce a line on the graph I plot

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Aaron Clewer on 10 Mar 2020
Commented: ME on 10 Mar 2020
When I run my code, results will appear but my results just won't show on the graph:
K = 1
i = sqrt(-1);
n=0;
for w = 0.1:1000
n=n+1;
A(n) = w;
G(n) = K/((i*w)*((i*w)+1.71)*((i*w)+100));
end
M(n) = abs(G(n));
F(n) = 20*log(M(n));
semilogx(w,F)

Ameer Hamza on 10 Mar 2020
Edited: Ameer Hamza on 10 Mar 2020
You were just plotting a single point. Check the indexing of variables after the for loop.
K = 1;
i = sqrt(-1);
n=0;
W = 0.1:1000;
for w = W
n=n+1;
A(n) = w;
G(n) = K/((i*w)*((i*w)+1.71)*((i*w)+100));
end
M = abs(G);
F = 20*log(M);
semilogx(W,F) ##### 2 CommentsShowHide 1 older comment
Ameer Hamza on 10 Mar 2020

ME on 10 Mar 2020
I'm not 100% sure but I'd guess you want the last line to be:
semilogx(A,F)
because otherwise everything is plotting at the same value on the x-axis.
##### 2 CommentsShowHide 1 older comment
ME on 10 Mar 2020
Plots over the whole range of the x-axis for me. I guess the issue is that the line is right along the edge of the figure window. If you change the view of the axes or the axes limits then you'll be able to see the line.