Re: Replacing Numbers in a List
- To: mathgroup at smc.vnet.net
- Subject: [mg68253] Re: Replacing Numbers in a List
- From: Jean-Marc Gulliet <jeanmarc.gulliet at gmail.com>
- Date: Mon, 31 Jul 2006 03:45:05 -0400 (EDT)
- Organization: The Open University, Milton Keynes, UK
- References: <eahsgh$op1$1@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
Gregory Lypny wrote:
> Hello everyone,
>
> I have a long list of integers called x, and I want to replace those
> that are members of list y with the number 222.
>
> I did it this way with a Do loop.
>
> y = {122, 211, 212, 221, 223, 232, 322};
> Do[x = ReplacePart[x,222, Position[x, y[[i]]]],{i, Length@y} ]
>
> Is this OK, or is there a more direct way?
>
> Regards,
>
> Gregory
>
What about transformation rules?
x= { 221,223,222,221,223,223,224,220,122,223}
y= { 122,211,212,221,223,232,322};
x/. p_/; MemberQ[ y,p]->222
returns {222, 222, 222, 222, 222, 222, 224, 220, 222, 222}
HTH,
Jean-Marc