Re: Testing the Head of List Elements
- To: mathgroup at smc.vnet.net
- Subject: [mg25250] Re: [mg25200] Testing the Head of List Elements
- From: Matt.Johnson at autolivasp.com
- Date: Sun, 17 Sep 2000 04:47:29 -0400 (EDT)
- Sender: owner-wri-mathgroup at wolfram.com
Marshall -
Use Cases:
In[75]:=
list = {1, 1.2, "abc", a, {3, 2, 1}};
In[76]:=
Cases[list, _String]
Out[76]=
{"abc"}
In[77]:=
Cases[list, _Integer]
Out[77]=
{1}
In[78]:=
Cases[list, _List]
Out[78]=
{{3, 2, 1}}
-matt
"Marshall Bartlett" <mgb_news at hotmail.com> on 09/15/2000 12:21:40 AM
cc:
Subject: [mg25250] [mg25200] Testing the Head of List Elements
I'm something of a newbie with Mathematica; please excuse my ignorance.
I am looking for a clever way to select elements from a list based on their
type (Head). Specifically, I want to extract all the elements of type
dtring from a list of elements of different types (string, number,
character, etc.).
Any suggestions?
--
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Marshall Bartlett
Department of Geology and Geophysics
University of Utah
mgb_news at hotmail.com
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