Re: Help needed with List!
- To: mathgroup at smc.vnet.net
- Subject: [mg16926] Re: Help needed with List!
- From: "P.J. Hinton" <paulh>
- Date: Thu, 8 Apr 1999 02:32:35 -0400
- Organization: "Wolfram Research, Inc."
- Sender: owner-wri-mathgroup at wolfram.com
On 6 Apr 1999 alvaroo at my-dejanews.com wrote:
> (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?
In[1]:= ? IntegerDigits
IntegerDigits[n] gives a list of the decimal digits in the integer n.
IntegerDigits[n, b] gives a list of the base-b digits in the integer n.
IntegerDigits[n, b, len] pads the list on the left with zeros to give a
list of length len.
In[2]:= IntegerDigits[123456]
Out[2]= {1, 2, 3, 4, 5, 6}
> (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}.
In[3]:= ? Complement
Complement[eall, e1, e2, ... ] gives the elements in eall which are not in
any
of the ei.
In[4]:= A = {1,2,3,4}
Out[4]= {1, 2, 3, 4}
In[5]:= B = {1,2}
Out[5]= {1, 2}
In[6]:= Complement[A, B]
Out[6]= {3, 4}
For more information on these functions, see _The Mathematica Book_ (Third
Edition). If you are using the Mathematica 3.0 notebook front end, you
may be able to retrieve this content using the Help Browser. Paste the
following expressions into a notebook and evaluate them.
FrontEndExecute[FrontEnd`HelpBrowserLookup["MainBook", {"3.1.3", "3.9"}]]
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--
P.J. Hinton
Mathematica Programming Group paulh at wolfram.com
Wolfram Research, Inc. http://www.wolfram.com/~paulh/
Disclaimer: Opinions expressed herein are those of the author alone.