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Re: Question about Mathematica

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  • Subject: [mg106568] Re: [mg106544] Question about Mathematica
  • From: Bob Hanlon <hanlonr at cox.net>
  • Date: Sat, 16 Jan 2010 06:13:59 -0500 (EST)
  • Reply-to: hanlonr at cox.net

data = {
   {{1, 2}, {3, -1}, {2, -4}},
   {{1, 2}, {4, -5}, {6, -8}},
   {{2, -1}, {-2, -3}, {-4, 6}}};

SortBy[#, Last][[1]] & /@ data

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

Cases[#, {_, Min[#[[All, -1]]]}][[1]] & /@ data

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

f[x_] := Select[x, #[[-1]] == Min[x[[All, -1]]] &]

First /@ f /@ data

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


Bob Hanlon

---- 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



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