# Right array division with a vector

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Harel Harel Shattenstein on 25 Mar 2018
Edited: John D'Errico on 25 Mar 2018
Why
1./1:1:10
return error
and
1./(1:1:10)
Does not?
Should not 1:1:10 return a vector?

John D'Errico on 25 Mar 2018
Edited: John D'Errico on 25 Mar 2018
Works for me.
1./1:1:10
ans =
1 2 3 4 5 6 7 8 9 10
What error do you think it produces?
Let me guess. it did not produce an error. It just produces something you did not expect to see.
Division is higher in the operator precedence list than colon.
So MATLAB computes 1./1, which happens to be 1. Then it generates the vector 1:1:10. Effectively, MATLAB sees this as
(1./1):1:10
When you change it by putting parens around the colon call, it does that FIRST, then divides those elements into 1.
So really, this is just a question of understanding operator precedence.
https://www.mathworks.com/help/matlab/matlab_prog/operator-precedence.html
If colon was higher in the list, then you would get the same answer with or without the parens.