Re:Select xs.t.y>10
- To: mathgroup at smc.vnet.net
- Subject: [mg13992] Re:Select xs.t.y>10
- From: Allan Hayes <hay at haystack.demon.co.uk>
- Date: Sat, 12 Sep 1998 16:59:16 -0400
- Sender: owner-wri-mathgroup at wolfram.com
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:
data= {{1,2},{2,6},{3,6}};
Cases[data,{x_,y_}/;y>5->x, {1},1]
{2}
Allan
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Allan Hayes
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