Re: Sort
- To: mathgroup at smc.vnet.net
- Subject: [mg19172] Re: Sort
- From: Jens-Peer Kuska <kuska at informatik.uni-leipzig.de>
- Date: Tue, 10 Aug 1999 02:52:38 -0400
- Organization: Universitaet Leipzig
- References: <7odl77$7of@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
Hermann Meier wrote:
>
> Sort is not reliable. Try the following (Mathematica Version 4):
>
> In[1]:=
> Sort[{0, -Sqrt[2], 5}]
>
Hi Hermann,
thats nonsense. If you cant only sort the same kind of things.
There is no rule how to sort a train, a airplane and a toaster.
In you example you try to sort integers and symbolic expressions
like Sqrt[5]. Sort[] work as expected and create the "normal order" of
expressions i. e.
numbers first, variables, functions ..
If you like to sort a list of numbers with some symbolic expressions
like Sqrt[2], E, Pi .. you can simply use the second sort argument and
Sort[{0, -Sqrt[2], 5}, N[#1] < N[#2] &]
will work as you expect.
Hope that helps
Jens