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Why am I getting "Undefined function or variable" when I use an exponential in the function?

Asked by Nicholas Gillam on 11 Apr 2019
Latest activity Commented on by John D'Errico
on 11 Apr 2019
My code worked for other functions, but as soon as I use the exponential function, I am getting an error saying that "I" is undefined, and I honestly have no idea why it's giving me an error only for the exponential function.
a = 0;
b = 1;
N = 10;
f = @(x) exp(-x);
j = 0;
for i = 1:N-1
answer1 = sum(I)


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1 Answer

Answer by James Tursa
on 11 Apr 2019

There is no "I" variable in your code. Hence the error.


Interestingly enough, I definied my f for a different problem and got the error initally stated, but the new problem doesn't have an exponential in it.
f = @(x) cos(4*cos(x)+x);
What does the exponential have to do with your problem of "I" not being defined?
I wonder if it is possible Nocholas has created a script of function named exp?

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