Re: Help needed with List!
- To: mathgroup at smc.vnet.net
- Subject: [mg16948] Re: Help needed with List!
- From: "Stephen P Luttrell" <luttrell at signal.dra.hmg.gb>
- Date: Thu, 8 Apr 1999 02:32:45 -0400
- Organization: Defence Evaluation and Research Agency
- References: <7ec5kg$cu2@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
>Sirs Probably these are FAQs but I am new in this newsgroup and I have not
>been able to solve them. I use Mathematica 3.0: (i) I need to convert a
long
>integer number in List format. For example if I had the number 123456 I
need
>to convert it into {1,2,3,4,5,6}: Is it possible with an instruction? And,
>(ii) I need to delete from a List A the common elements with other List B:
>for example if A = {1,2,3,4} and B = {1,2} I need to delete by an
instruction
>the elements 1, 2 of List B from List A to obtain List C = {3,4}. I am
>working with integers with 10.000 digits or more so you can appreciate how
>helpful for me it would be to solve these questions. Thanks in advance.
>alvaroo
Here is a solution:
In[1]:=IntegerDigits[123456 ]
Out[1]={1,2,3,4,5,6}
In[2]:=
A = {1,2,3,4} ;
B = {1,2} ;
Select[A,FreeQ[B,#]&]
Out[2]={3,4}
Stephen P Luttrell
Signal Processing and Imagery Department
DERA Malvern, St.Andrew's Road
Malvern, United Kingdom, WR14 3PS
+44 (0)1684 894046 (tel)
+44 (0)1684 894384 (fax)
luttrell at signal.dera.gov.uk (email)