Re: [igraph] how to plot a very basic MST with igraph

[Steve Boudreault]

>
> Maybe you want this:
> http://en.wikipedia.org/wiki/Euclidean_minimum_spanning_tree
> Do you?
>


Yes, this is correct.


>
> What is the rule to connect the
> dots?
>


In the link you gave me, I see the following sentence : << [...] an EMST
(Euclidean minimum spanning tree) connects a set of dots using lines such
that the total length of all the lines is minimised and any dot can be
reached from any other by following the lines. >>

Isn't that the rule? i.e. that my objects in the RA vs DEC place are
connected such that the total length of all the lines is minimised?

I can add that all my objects have the same weight.


>
> On Wed, Mar 5, 2014 at 11:17 AM, Steve Boudreault
> <address@hidden
>> wrote:
>> > But I'd prefer you tell us want you want to do, and then we don't
need
>> > to
>> > guess.
>> Please look at the following image :
>> http://inspirehep.net/record/833443/files/mst.png
>> These are "minimum spanning tree" (right?) of stars distributed in X (i.e.
>> right ascension, RA) and Y (i.e. declination, DEC). You have this for
three open clusters : IC2391, M34, M11.
> Again. The minimum spanning trees in igraph are defined for graphs
(=networks), not for points:
> http://en.wikipedia.org/wiki/Minimum_spanning_tree
> Maybe you want this:
> http://en.wikipedia.org/wiki/Euclidean_minimum_spanning_tree
> Do you?
> This *is* what I want to do. I want to do a plot like this.
> This is not an explanation, I am sorry. What is the rule to connect the
dots? Maybe this is evident for people in your field, but not to me. G.
> [...]


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Steve Boudreault, Ph.D.
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