Re: comparison operators

[Douglas Eck]

> In fact, all you need is to ask for a([1 1 1 1 1])
> and you get the first element repeated.
>
> This can only be a bug ; and by its nature will
> invalidate all simulations of random processes
> which involve such a step.

This may be a bit strong. Consider this example

octave:40> a=rand(1,5);

octave:41> idx=a>0
idx =

        1        1        1        1        1

octave:42> a(idx)
ans =

  0.00284  0.18795  0.84289  0.56375  0.24161


octave:43>a([1 1 1 1 1])
ans =

  1.0e-03  *

  2.83558  2.83558  2.83558  2.83558  2.83558


As I understand it, this isn't a bug. Nor is it random.
The > operator returns a boolean vector, while "[1 1 1 1 1]" is a
regular (non-boolean) vector

octave:46> is_bool(idx)
ans = 1

octave:47> is_bool([1 1 1 1 1])
ans = 0

In any case, it's best to use find().

Ciao,
Doug



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