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Re: List handling

• To: mathgroup at smc.vnet.net
• Subject: [mg15277] Re: List handling
• From: "Allan Hayes" <hay at haystack.demon.co.uk>
• Date: Thu, 31 Dec 1998 04:39:32 -0500
• References: <76ciqj$o51@smc.vnet.net>
• Sender: owner-wri-mathgroup at wolfram.com

Jorge Zickermann wrote in message <76ciqj$o51 at smc.vnet.net>...
>...........
>Having obtained the positions of certain selected elements from ListB, I
>want to substitute the corresponding elements in ListA by the
>corresponding elements in ListC.
> ..........

Jorge:

listA = {1, 2, 3, 4};
listB = {3, 2 , 5, 1};

Flatten[Position[listB, _?(# > 2 &)]]

{1, 3}

listA [[%]] = listB[[%]];

listA

{3, 2, 5, 4}

If the lists might not be of the same lenght then we can use

listB = {3, 2 , 5, 1, 7};

Cases[Flatten[Position[listB, _?(# > 2 &)]], _?(# <= Length[listA] &)]

{1, 3}


Allan

---------------------
Allan Hayes
Mathematica Training and Consulting
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hay at haystack.demon.co.uk
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