Re: Cases
- To: mathgroup at smc.vnet.net
- Subject: [mg50447] Re: [mg50423] Cases
- From: Bob Hanlon <hanlonr at cox.net>
- Date: Sat, 4 Sep 2004 01:43:23 -0400 (EDT)
- Reply-to: hanlonr at cox.net
- Sender: owner-wri-mathgroup at wolfram.com
If d is a Symbol, Not[d] is not a boolean
Not[d]
¬d
x={a,b,c,d,d};
Cases[x,_?(!(#===d)&)]
{a, b, c}
Select[x,!(#===d)&]
{a, b, c}
Bob Hanlon
>
> From: "Blimbaum, Jerry AA R22" <jerry.blimbaum at navy.mil>
To: mathgroup at smc.vnet.net
> Date: 2004/09/03 Fri AM 03:35:08 EDT
> To: mathgroup at smc.vnet.net
> Subject: [mg50447] [mg50423] Cases
>
>
> Given: x = {a,b,c,d,d};
>
> Applying Cases[x,d] gives an output of {a,b,c}......
>
> However, Cases[x,Not[d]] gives as output an empty list { }... I
> expected {a,b,c}.....
>
> Why didnt I get that?
>
> This issue came up when using Thread on vectors...and in some cases the
> Thread resulted in 0 == 0 so it's output in the list was
> True....and I
> wanted to remove them....
>
> thanks.....jerry blimbaum
>
>