matlab strange behaviour of function sum()

Question

Any idea why Matlab could behave like this?

>> sum([0 0 0])
Subscript indices must either be real positive integers or logicals.

>> sum([1 1 1])

an         


        

Answer 1

you've overridden the function sum and now it is considered a local variable

 sum = s(1, 1);

thus you are hiding sum as function.

Change the variable name and do

 clear sum

.