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Re: Position of element in a list

• To: mathgroup at smc.vnet.net
• Subject: [mg16360] Re: [mg16301] Position of element in a list
• From: "Martin W. Mak" <mwmak at ix.netcom.com>
• Date: Thu, 11 Mar 1999 02:16:37 -0500
• Organization: Harmonic Systems
• References: <199903070605.BAA23750@smc.vnet.net.>
• Sender: owner-wri-mathgroup at wolfram.com

Roger,

    You might try:

            Position[Negative /@ {-1,3,-2,1},True]//Flatten

Roger Mason wrote:

> Hi,
>
> I want to find the Position[] of negative elements in a list. The obvious
> methods do not work:
>
> Position[{-1, 3, -2, 1}, -_]
>
> and
>
> Position[{-1, 3, -2, 1}, -x_]
>
> return
>
> {}
>
> So how do I perform this apparently simple task?
>
> Thanks,
>
> Roger Mason

• References:
  • Position of element in a list
    • From: Roger Mason <rmason@sparky2.esd.mun.ca>