# basic plotting need help

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Caner Bulduk on 2 May 2015
Answered: VBBV on 2 Oct 2021
i have a function;
H = (wo*w)/sqrt(w*w*wo*wo + Q^2*wo^4 + Q^2*w^4-2*Q^2*w^2*wo^2
where;
Q=20;
wo=[7596.4 8394.3];
i create a function for that
function [output]=H(w,wo,Q)
output =(wo*w)/sqrt(w*w*wo*wo + Q^2*wo^4 + Q^2*w^4-2*Q^2*w^2*wo^2);
end
when i try to use function for calculate some values
"Subscript indices must either be real positive integers or logicals."
i got this.
How can i plot this function and whats the mean of that error?
Thanks a lot for your help

Ahmet Cecen on 3 May 2015
This might not be your only problem, but if o0 is a row vector as you wrote there, you have:
w*w*wo*wo
as a term, where wo*wo is undefined as a vector operation, and also
+ Q^2*wo^4
wo to the power 4 is undefined similarly.

VBBV on 2 Oct 2021
% syms wo w Q
Q=20;wo=[7596.4 8394.3];w = 10;
K = H(w,wo,Q)
output = 1×2
1.0e+-4 * 0.6582 0.5956
K = 1×2
1.0e+-4 * 0.6582 0.5956
% H = @(wo,w,Q) (wo*w)/sqrt(w*w*wo.*wo + Q^2*wo.^4 + Q^2*w^4-2*Q^2*w^2*wo.^2
plot(K,'-b','linewidth',6) function [output]=H(w,wo,Q)
output =(wo*w)./sqrt(w*w*wo.*wo + Q^2*wo.^4 + Q^2*w^4-2*Q^2*w^2*wo.^2)
end
Try this