Thread Subject: Vector - change all 1's to -1

I have a random vector of ones and zeros.
How do I change the 1's to -1's

On Wed, 18 Nov 2009 15:28:19 -0500, happydude <anonymousse@hotmail.com>
wrote:

> I have a random vector of ones and zeros.
> How do I change the 1's to -1's

Multiply by -1?

crikey... ive been looking at this screen way too long..

how do i delete a post from this thing :)

(thanks btw)

happydude wrote:
> crikey... ive been looking at this screen way too long..

For the specific problem, the -1* solution is probably the quickest.

But, just for pedagogical reasons, the more generic way could be

x(x==1) = -1

for cases where a transformation doesn't work. It's "logical
addressing", a very powerful ML implementation.

> how do i delete a post from this thing :)

You don't -- despite the gui interface at TMW, c.s-s-.m is a usenet
group and postings are spread to multitude of servers just to make sure
everybody sees... :)

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