Clear Filters
Clear Filters

How to solve "index exceeds the number of array elements"

2 views (last 30 days)
Hi,
Why I can't plot the following code? The error is: Index exceeds the number of array elements (1).
What I'm trying to achive is that a user enters a scalar value f (such as 1500) anf Ht and Hr. So, I want to find value of ahr and L accondingliy and then plot L vs f. SO on f axis I shoud have 100,150,200,250,300,....,1500 and corrsponding values on L axis.
for i=100:50:f
cm=0;
ahr(i)=(1.1*log10(f(i))-0.7)*Hr-1.56*log10(f(i))-0.8;
L(i)=46.3+33.9*log10(f(i))-13.82*log10(Ht)-ahr+(44.9-6.55*log10(Hr))*log10(d)+cm;
plot(f,L)
end

Accepted Answer

Mischa Kim
Mischa Kim on 24 Dec 2020
Edited: Mischa Kim on 24 Dec 2020
Hi Ryan, try something like this:
fl = 100;
fu = 1500; % replace as necessary
N = 100;
f = linspace(fl,fu,N);
cm = 0;
for ii = 1:numel(f) % careful with "i", this is also the imaginary unit
ahr(ii) = (1.1*log10(f(ii))-0.7)*Hr-1.56*log10(f(ii))-0.8;
L(ii) = 46.3+33.9*log10(f(ii))-13.82*log10(Ht)-ahr(ii)+(44.9-6.55*log10(Hr))*log10(d)+cm;
end
plot(f,L)
  3 Comments
Mischa Kim
Mischa Kim on 24 Dec 2020
Edited: Mischa Kim on 24 Dec 2020
With
for i=100:50:f
i is assigned values: 100, 150, 200, 250, etc. As a result, in
L(ii) = 46.3+33.9*log10(...
you create a (rather long) vector L and assign values to L(100), L(150), and so on and so forth. At the same time, f is a scalar (just one number). For the plot() command to work f and L need to be vectors of the same size.

Sign in to comment.

More Answers (0)

Products

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!