MATLAB: Subscript indices must either be real positive integers or logicals

logicalspositive integers

Greetings all,

Well, I've never seen this error before, and I did try making my imaginary parts real – still didn't help.

Here's my code if you will (the relevant parts, all things not shown are previously defined):

D = [5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25];
skin_depth_seawater = sqrt(2/sigma_helo_seawater*u*omega);
F_1 = 1;
r = sqrt(eta^2+i*omega*sigma_helo_seawater*u); 
V_1 = sqrt(r^2 + (2*i*sigma_helo_seawater/sigma_helo_seawater));
R(D,r) = real(V_1*F_1 - r)/(V_1*F_1 + r); %****

Now when I run the file, it gives me the "subscript indices must either be real positive integers or logicals" error at the line where I have **.

Can someone explain what I am doing wrong and where I need to correct it?

Thanks!

Best Answer

r = sqrt(eta^2+i*omega*sigma_helo_seawater*u);

will almost never be a positive integer, but you try to use r as a subscript in the output of the assignment.

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Am I right that your function, f, looks something like this?

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        more code 
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If so it cannot possibly run, because the variables, D and A, are not assigned values in the workspace of the function. The messaqe, "Undefined function or variable 'D'", reports this problem. From Matlabs point of view there could have been a function named, D, in the search path. BTW: "f" is not a good name of a function. Next time Matlab will find it when you forget to pass the variable, "f".

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Am I right that you have two functions and one script:

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    code
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I cannot see the connection between the functions and the script. The call

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doesn't engage the script.

Over

Best Answer

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