• To: mathgroup at smc.vnet.net
• Subject: [mg106565] Re: [mg106544] Question about Mathematica
• From: DrMajorBob <btreat1 at austin.rr.com>
• Date: Sat, 16 Jan 2010 06:13:24 -0500 (EST)
• References: <201001151200.HAA07995@smc.vnet.net>

```data = {{{1, 2}, {3, -1}, {2, -4}}, {{1,
2}, {4, -5}, {6, -8}}, {{2, -1}, {-2, -3}, {-4, 6}}};
Reverse /@ (Sort /@ Map[Reverse, data, {2}])[[All, 1]]

{{2, -4}, {6, -8}, {-2, -3}}

or

(SortBy[#, Last] & /@ data)[[All, 1]]

{{2, -4}, {6, -8}, {-2, -3}}

Bobby

On Fri, 15 Jan 2010 06:00:46 -0600, Dominic <miliotodc at rtconline.com>
wrote:

> Hi.  Can someone help me with the following question:
>
> I have a table of a table of number pairs:
>
> {{{1,2),(3,-1),{2,-4)},{{1,2},{4,-5},{6,-8}},{{2,-1},{-2,-3},{-4,6}}}
>
> How may I find the minimum second element in each sub-table?  For
> example, the first sub-table is:
>
> {{1,2},{3,-1},{2,-4}}
>
> I would like to then extract the {2,-4} element from this item.  Then
> the {6,-8} from the second sub-table, then the {-2,-3} element from the
> last.
>
> Thank you,
> Dominic
>
>

--
DrMajorBob at yahoo.com

```

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