Re: logical indexing shortcut?

[Peter P.]

Addon to my prevous posting below:

* Peter P. <address@hidden> [2017-09-03 18:02]:
> Hi list,
> 
> I am looking for a way to operate on certain elements of a vector using
> logical indexing. I want to multiply all elements in x that are integer
> multiples of four by the number 5.
> 
> x = [3 15 9 12 -1 0 -12 9 6 1];
> b = rem(x, 4)==0;
> x(b) = x(b)*5
> 
> I wonder if there is a way to do it in one step, without creating index
> vector b?
and without calculating the condition twice, as in
x(rem(x, 4)==0) = x(rem(x, 4)==0) * 5

thanks,
P