Re: more with lists
- To: mathgroup at smc.vnet.net
- Subject: [mg40339] Re: [mg40326] more with lists
- From: Andrzej Kozlowski <akoz at mimuw.edu.pl>
- Date: Wed, 2 Apr 2003 04:35:25 -0500 (EST)
- Sender: owner-wri-mathgroup at wolfram.com
Let, for example,
ls=Table[{Random[],Random[]},{10}]
{{0.674904,0.947432},{0.712511,0.325852},{
0.895512,0.674274},{0.472473,0.430607},{
0.360706,0.529332},{
0.42937,0.52123},{0.60123,0.619804},{0.415462,0.3121},{0.778426,0.738771
},\
{0.453092,0.290448}}
One way:
Cases[ls,{x_,y_}/;x<0.5&&y>0.4]
{{0.472473,0.430607},{0.360706,0.529332},{0.42937,0.52123}}
Another way:
Select[ls,First[#]<0.5&&Last[#]>0.4&]
{{0.472473,0.430607},{0.360706,0.529332},{0.42937,0.52123}}
(There are also several other variations of these two basic methods.)
Andrzej Kozlowski
Yokohama, Japan
http://www.mimuw.edu.pl/~akoz/
http://platon.c.u-tokyo.ac.jp/andrzej/
On Tuesday, April 1, 2003, at 06:52 pm, Nathan Moore wrote:
> The replies have been beautiful!
>
> suppose I have a list of n {x,y}pairs. I'd like to cull the list into
> a
> smaller list for which the condition x<Xo, y>Yo is true. If the list
> was
> 1-D I could simply use "Select," how do I access the data points in
> pairs?
>
> Nathan Moore
> Universoty of Minnesota Physics
>
>
>
>