Re: Adding value to some elements of a list
- To: mathgroup at smc.vnet.net
- Subject: [mg131059] Re: Adding value to some elements of a list
- From: Daniel <dosadchy at its.jnj.com>
- Date: Thu, 6 Jun 2013 23:18:28 -0400 (EDT)
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- Delivered-to: l-mathgroup@wolfram.com
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If you want to do it in place, then:
In[1]:= a[[b]] += c;
In[2]:= a
Out[2]= {10, 37, 30, 57, 50, 77}
> Hello,
>
> I have two lists. One containing values, another
> containing indexes to
> the first list. I want to add a value to all elements
> of the first list
> when its index is in the second list:
>
> a={10,20,30,40,50,60}
>
> b={2,4,6}
>
> c=17
>
> ==>
>
> {10,20+17,30,40+17,50,60+17}
>
> I would be glad if anyone have a simple solution for
> that problem - I am
> convinced there is one ...
>
> Best regards
> J. Lenhardt
>