Re: Testing the Head of List Elements
- To: mathgroup at smc.vnet.net
- Subject: [mg25257] Re: [mg25200] Testing the Head of List Elements
- From: Tomas Garza <tgarza01 at prodigy.net.mx>
- Date: Sun, 17 Sep 2000 04:47:41 -0400 (EDT)
- Sender: owner-wri-mathgroup at wolfram.com
Suppose your list is something like {"letter",1,a}. The first element is
a string.
In[3]:=
Select[{"letter", 1, a}, Head[#] == String &]
Out[3]=
{"letter"}
This does what you want (it's really not too clever, though).
Tomas Garza
Mexico City
"Marshall Bartlett" <mgb_news at hotmail.com> wrote:
> 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.).