Re: Select x s.t. y>10
- To: mathgroup at smc.vnet.net
- Subject: [mg14001] Re: Select x s.t. y>10
- From: Leszek Sczaniecki <lsczan at concentric.net>
- Date: Sat, 12 Sep 1998 16:59:23 -0400
- Organization: Concentric Internet Services
- References: <6tbtv8$mq0@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
Is there any reson that you can't use directly a build-in function
Select as in the following example?
In[1]:=
lst = Table[{Random[], Random[]}, {10}] Out[1]=
{{0.87642,0.859277},{0.990313,0.434662},{0.631448,0.153609},{0.515145,
0.424282},{0.00339491,0.575325},{0.562473,0.690501},{0.817277,0.713543},{
0.709017,0.351955},{0.937637,0.0728005},{0.553451,0.791334}}
In[1]:=
Select[lst, #[[2]] < .5 &]
Out[1]=
{{0.990313,0.434662},{0.631448,0.153609},{0.515145,0.424282},{0.709017,
0.351955},{0.937637,0.0728005}}
-- Leszek
Jason Gill wrote:
> I came across what seems like it should be a simple little function, but
> could not come up with a clever way to implement it. Generally, what I
> am trying to do is take a list of lists of length 2 ie a list of x,y
> coordinates, and Select x values based on some criterion for y. For
> example I want to select the first x value for which the corresponding
> y is greater than 5.
> I can write a function using Position and Take etc. , but there must be
> a clever,and more efficient way to do this. Any thoughts... Jason
>
> --
> Jason Gill
> IBM Microelectronics
> Essex Junction, VT 05452
> Phone (802)769-3350
> Fax (802)769-1220
> email: jgill at vbimail.champlain.edu
> jasongil at us.ibm.com