# How to get number of factors after factorizing a symbolic function?

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Bill Tubbs on 6 Jul 2020
Commented: Bill Tubbs on 6 Jul 2020
I'm using factor to factorize a symbolic polynomial.
Works well but when the result is a symbolic vector containing the factors, I'm not sure how to determine how many factors it contains. I tried using size but I get some inconsistent results:
>> G(s) = s^2 + 3*s + 2;
>> F = factor(G, s)
F(s) =
[ s + 2, s + 1]
>> size(F)
ans =
1 1
>> F = factor(G(s), s)
F =
[ s + 2, s + 1]
>> size(F)
ans =
1 2
>>
Note, the size is different in the second example. The only difference is that I used factor(G(s), s) rather than factor(G, s). What is the difference and why does the result (F) look the same but the size is not the same?
##### 2 CommentsShowHide 1 older comment
madhan ravi on 6 Jul 2020
Now you don’t see Star’s answer below.

madhan ravi on 6 Jul 2020
numel(formula(F)) % will avoid confusions ;)
Bill Tubbs on 6 Jul 2020
This seems to work whether F is an expression or a function. Thanks!

R2019b

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