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RE: Simple Question -- Incrementing All Elemnts in A li st by 1

• To: mathgroup at smc.vnet.net
• Subject: [mg44333] RE: [mg44290] Simple Question -- Incrementing All Elemnts in A li st by 1
• From: David.Annetts at csiro.au
• Date: Wed, 5 Nov 2003 10:01:33 -0500 (EST)
• Sender: owner-wri-mathgroup at wolfram.com

Hi Thiery,

> I would like to have all elements in a list incremted by a 
> given number
> without defining a supplementary function.
> 
> What I've done so far is:
> 
> incFunc[n_]:=n+1;
> Map[incFunc,{2,3,4,45,98}]
> 
> which is all fine. It is only that I'm looking for a solution 
> _without_
> defining the mentioned function incFunc.

Something like ...
lst = Table[Random[Integer, {0, 100}], {100000}];
Timing[in1 = (++lst[[#]])& /@ Range[Length@lst];]
Timing[in2 = (# + 1)& /@ lst;]

should suffice.  in2 appears in general faster than in1.

Regards,

Dave.