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Re: Better Way of Testing and Replacing List Elements?

• To: mathgroup at smc.vnet.net
• Subject: [mg103968] Re: [mg103949] Better Way of Testing and Replacing List Elements?
• From: Adriano Pascoletti <adriano.pascoletti at dimi.uniud.it>
• Date: Wed, 14 Oct 2009 07:54:59 -0400 (EDT)
• References: <200910140319.XAA22469@smc.vnet.net>

In[2]:= xxx = {1, 2, 3, 4, 5, -6, -7, 8, 9, 10, -1, 11, 12};
  xxx /. {x_ /; x < 0 -> 0}
Out[2]= {1, 2, 3, 4, 5, 0, 0, 8, 9, 10, 0, 11, 12}


Adriano Pascoletti

2009/10/14 careysub <careysub at gmail.com>

> The code below replaces the negative values in a list with zero, and
> is an example of a type of operation I use a lot:
>
> xxx = {1, 2, 3, 4, 5, -6, -7, 8, 9, 10, -1, 11, 12};
> ReplacePart[xxx, Position[Map[Negative, xxx], True] -> 0]
>
> Is there a "better" way of doing this (fewer function calls, more
> efficient)?
>
> My feeling is that I'm doing this in an awkward way.
>
>

• References:
  • Better Way of Testing and Replacing List Elements?
    • From: careysub <careysub@gmail.com>