On Wed, 19 Nov 1997, Graph Theory Project wrote:
> Hi:
>
>
> 1. in LINK: Graph View, there is a menu called Graph-View, when I draw
> a graph, then click the redraw, after a while, there will blick once,
> then nothing all happened, and also when I click the refresh graph,
> nothing all happened, I think it is because I do not know how to use
> it. can you tell me?
Redraw is mainly useful after the window has been resized. It updates the
viewing transformation from world to viewing coordinates.
>
> 2.on LINK: graph view, there is a menu Layout, under Layout, there is
> Edge Draw, I tried, but it seemed it has no effect on the picture,
> perhaps I am wrong in using it. can you tell me how I can use it correctly?
>
Edge draw is only interesting when viewing hypergraphs. Hyperedges are
drawn either as paths or stars.
> 3. when I tried the web example (An example Scheme/Tk session(which sets
> edge weights, finds a minimum spanning tree...), I have the error:
>
> STk> (define g (graph *link:selected-graph-view*))
>
> *** Error:
> unbound variable: make-graph
>
> I do not know why?
Probably you haven't selected the graph view by clicking in it with the
left button.>
> 4. now I have already finished reading all the examples on the web,
> and I have some questions.
>
> A: in "Graph Drawing and Manipulation with LINK"
> I tried the Figure3.
> first I draw the graph, then I typed:
>
> STK>(describe (graph (current-graph-view)))
>
> *** Error:
> unbound variable: make-graph
>
> why?
Same reason as the last.
>
> B: I tried figure 4 and figure 5, all only I have just the result
> for example: ....val={{1 2} {2 3}}
> (38.0 13.0)
>
> , How I can get the graph of it ?
(define tree (graph (vertices (graph gv)) (kruskal (graph gv))))
>
>
> C: about the figure 6, which is abou the Binding the "f" key
> so that the forefather of a selected vertex is flashed.
>
> I typed all the stk code, then the result is just:
> #undefined, how I can see its use on interface?
Did you try selecting vertices and typing f? The forefather should be
flashed.
>
> aslo in articel:
>
> Improving Discrete Mathematics and Algorithms Curricula with LINK.
>
> I tried the figure 3: A random walk function,
> I also typed the code, also the result is #undefined,
> I can not see any interface which illustrated this randow walk, How I
> can see it from the LINK GUI?
Once it is defined, type (random-walk (current-graph-view))
after you have clicked with the left button in a graph window (to select it).
The #undefined is simply the return value of the (define...) function, which
doesn't return anything.
>
> D:
> about the Latka Tournaments, because I lack some knowledge about the
> discrete mathematics, I see some book, but some concepts I still
> do not understand, I am not clear about the useage of this Latka
> tourment, in real world, what is the detail advantage of this Latka
> Tourment.
>
Real world: this study is giving us better insight into things called
"well quasi-orderings." These contributions won't be reflected in the
next release of Microsoft Windows, but in the long run, we'll know more
mathematics.
>
> I have some other questions about articles. I will summary it and send
> E-mail to you later.
>
>
>
> Thanks!
>
>
> Liu Mei
>
>