Re: [PLUG] Topics for PLUG in January

[Walt Mankowski via plug <plug@lists.phillylinux.org>]

The only one of those topics I've studied is network flows. I could
definitely talk about that, but it feels more advanced than what I was
envisioning. I was thinking about more of a "Graph Theory 101" talk to
go over the basics.

I think it's important to understand the algorithms, but for most
developers I think I think it's far more important to recognize a
problem as something than can be modeled as a graph, and then knowing
how to use a graph library to help you solve it. As an example, in one of
the problems in this year's Advent of Code [1] you were given a grid
of numbers and had to find a path from the upper left to lower right
corners such that the sum of all the cells you pass through was as low
as possible.

Step 1 in solving it is realizing you can think of the grid as a graph
where each number is a node, and the edges are each cells
neighbors. Once you've done that, there are a number of different
shortest path algorithms you can use. One of the most popular is
called Dijkstra's Algorithm, and some friends mentioned that they had
to look it up and see how to implement it. All I did was load all the
edges into networkx (another Python graph module) and then call
nx.dijkstra_path_length().

Walt

1. https://adventofcode.com/2021/day/15

On Mon, Jan 03, 2022 at 09:18:20AM -0500, Lynn Bradshaw via plug wrote:
> Oddly enough, I was attempting to install graph-tool just as I read
> the idea. The preface in the book "Complex Network Analysis in Python"
> mentions which sort of topics will or won't be covered, like so: "Many
> discipline-specific aspects, such as triadic census, exponential
> random graph models (ERGMs), and network flows, as well as the whole
> story of network dynamics (evolution and contagion), have been
> intentionally left uncharted." So exactly what angle you have strikes
> me as important. Like for another instance, would it be more about how
> the subject would typically be taught in a discrete math course or
> will NetworkX and such tools come into the picture (i.e. more so
> implementation than theory)? The latter approach might be better.
> 
> On Sun, Jan 2, 2022 at 8:10 PM Walt Mankowski via plug
> <plug@lists.phillylinux.org> wrote:
> >
> > I should add that since I haven't actually written a graph theory
> > talk, that wouldn't be ready until at least February.
> >
> > On Sun, Jan 02, 2022 at 06:43:37PM -0500, Walt Mankowski via plug wrote:
> > > Hi everyone,
> > >
> > > I hope everyone enjoyed the holidays. If you were able to take some
> > > time off, I hope you found it relaxing.
> > >
> > > Our next PLUG meetings are Central this coming Wednesday, January 5,
> > > and North next Tuesday, January 11. We don't have any speakers lined
> > > up. If anyone would like to give a talk, please let me know.
> > >
> > > Here are a few topics I've been toying with:
> > >
> > > * We've had a bunch of new folks in the meetings the past few months,
> > >   and I'd be willing to do one of my older talks if anyone's
> > >   interested. You can see them all at http://www.phillylinux.org/talks.html
> > >
> > > * A discussion of this year's Advent of Code [1], which I just
> > >   finished this afternoon.
> > >
> > > * Some basic graph theory was helping in solving a number of the AoC
> > >   problems this year. Would anyone be interested in a Intro to Graph
> > >   Theory talk?
> > >
> > > * Will 2022 finally be the Year of Linux on the Desktop? Or will it be
> > >   the year of Electron on the Linux Desktop?
> > >
> > > Walt
> > >
> > > 1. https://adventofcode.com/
> >
> >
> >
> > > ___________________________________________________________________________
> > > Philadelphia Linux Users Group         --        http://www.phillylinux.org
> > > Announcements - http://lists.phillylinux.org/mailman/listinfo/plug-announce
> > > General Discussion  --   http://lists.phillylinux.org/mailman/listinfo/plug
> >
> > ___________________________________________________________________________
> > Philadelphia Linux Users Group         --        http://www.phillylinux.org
> > Announcements - http://lists.phillylinux.org/mailman/listinfo/plug-announce
> > General Discussion  --   http://lists.phillylinux.org/mailman/listinfo/plug
> ___________________________________________________________________________
> Philadelphia Linux Users Group         --        http://www.phillylinux.org
> Announcements - http://lists.phillylinux.org/mailman/listinfo/plug-announce
> General Discussion  --   http://lists.phillylinux.org/mailman/listinfo/plug

Attachment: signature.asc
Description: PGP signature

___________________________________________________________________________
Philadelphia Linux Users Group         --        http://www.phillylinux.org
Announcements - http://lists.phillylinux.org/mailman/listinfo/plug-announce
General Discussion  --   http://lists.phillylinux.org/mailman/listinfo/plug