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Re: how to make a list of rules with 2 other lists composed by different kinds of elements

  • To: mathgroup at smc.vnet.net
  • Subject: [mg127140] Re: how to make a list of rules with 2 other lists composed by different kinds of elements
  • From: Alexei Boulbitch <Alexei.Boulbitch at iee.lu>
  • Date: Mon, 2 Jul 2012 05:26:20 -0400 (EDT)
  • Delivered-to: l-mathgroup@mail-archive0.wolfram.com

Dear all,

I want to generate a list composed by rules. That is,

I have two list
First one:
list1=={1, 2, 3}
The elements of this list are Integers.
Map[Head, list1] == {Integer, Integer, Integer}

Second one:
list2== {"file1", "file2", "file3"}
The elements of this list are Strings.
Map[Head, list2] == {String, String, String}


What I want is to have a new list like
list3== {1 -> "file1", 2 -> "file2", 3 -> "file3"}
Map[Head, list3] == {Rule, Rule, Rule}

Yes, of cause I can generate a list of rule manually. But what I have are
two big list of many elements and they are the output of other codes. So,
in real life this would be a part of big program. That is why I want to
generate the rule list automatically from list1 and list2. How could I do
this in a simple way? Thank you for your help.

Best regards,
Joug

Hi, Joug,

Try this:

list1 == {1, 2, 3};
list2 == {"file1", "file2", "file3"};

Thread[list1 -> list2]

{1 -> "file1", 2 -> "file2", 3 -> "file3"}

Or this:

Table[Rule[list1[[i]], list2[[i]]], {i, 1, Length[list1]}]

{1 -> "file1", 2 -> "file2", 3 -> "file3"}

Have fun, Alexei


Alexei BOULBITCH, Dr., habil.
IEE S.A.
ZAE Weiergewan,
11, rue Edmond Reuter,
L-5326 Contern, LUXEMBOURG

Office phone :  +352-2454-2566
Office fax:       +352-2454-3566
mobile phone:  +49 151 52 40 66 44

e-mail: alexei.boulbitch at iee.lu





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