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## [Help-glpk] pick element from set?

**From**: |
Kevin Hunter |

**Subject**: |
[Help-glpk] pick element from set? |

**Date**: |
Sun, 01 Jul 2012 03:11:00 -0400 |

**User-agent**: |
Mozilla/5.0 (X11; Linux x86_64; rv:13.0) Gecko/20120615 Thunderbird/13.0.1 |

Hello GLPK List,

`Is there a method to pick an arbitrary single item from a set? I don't
``care which one, but I need to have a single element from a set such that
``I can uniquely and consistently identify it.
`

`There is no order to the set, but /if/ there were an ordering to this
``set, I might reference this element as "nought". Put differently, say I
``have a set X:
`
set X, dimen 2 := {(5, 7), (1, 10), (23, -3), ("y", "x"), ("a", "abc")};

`Is there functionality -- say a function called "pick()" -- to pick an
``arbitrary element from that set?
`
Put another way, /if/ I could put that set into a list:
list(X) == [(5, 7), (1, 10), (23, -3), ("y", "x"), ("a", "abc")]
then I could get an arbitrary element, perhaps like 'get(list(X), 0)'.
Is there a method to grab a single element from the set?

`I'll point out that I have an ad-hoc method of this for a
``single-dimensional set (using a nested setof structure and a comparison
``operator), but can't do it for any higher-dimensionality sets.
`
Thanks,
Kevin

**[Help-glpk] pick element from set?**,
*Kevin Hunter* **<=**