Why do I get Inf for this complex expression?

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Daniel Montgomery on 2 Jun 2020
Answered: Ayden Clay on 2 Jun 2020
I have a function that generates a complex number but I get Inf for x. how could this be, if I do not make a logical error
for f=1:100
%a and b are struct passed by value, e.g. sturct(1).field
[R1,R2] = Prop(a(f),b(f),f,constant(f))
{e1=cell2mat(a)+cell2mat(b);
e2=cell2mat(a)-cell2mat(b);
w=(1-e1.*e2)./(e1-e2);}
end
David Goodmanson on 2 Jun 2020
Hi Daniel,
if you mean that you get inf for w, then on the basis of the information given the most obvious possibliity is that for at least one value of f the value of cell2mat(b) is zero.

Ayden Clay on 2 Jun 2020
Hi Daniel,
So in MATLAB there are only a few ways to get an output of "inf". The most common in equations is that we are dividing by zero.
In this case since w = (1-e1*e2)/(e1-e2), it must be the case that for some f, e1 = e2. This can only be the case if a+b = a-b which is only possible if b = -b, which is only possible if b = 0.