
A free graph theory book by David Joyner, Minh Van Nguyen, and Nathann Cohen - mononcqc
http://code.google.com/p/graph-theory-algorithms-book/
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ableal
Looks nice. I went into the tarball, looking for the Sage code snippets (they
seem to be only inline in the Tex files). Then, besides the possibly redundant
.hg dir, I noticed there were no image files for the figures. Those are _also_
inline, with "{tikzpicture}"

Seems to be a fairly recent thing. Found this 2006 paper:
<http://www.tug.org/TUGboat/Articles/tb28-1/tb88mertz.pdf>

P.S. This seems good enough to fetch all the Sage listings:

    
    
        sed -e '/begin.lstlisting/,/end.lstlisting/p' -e d *.tex
    

(Just in case it's handy for someone else. I always forget how 'sed' ranges
work.)

P.P.S. The PGF/TikZ graphics for TeX seem to have been first released in 2005:
<http://sourceforge.net/projects/pgf/> . These things sneak up on you when you
are not looking ... Google even tells me there's an "Inkscape extension for
exporting SVG paths as TikZ code"

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ximeng
This is the same book as the one mentioned in

<http://news.ycombinator.com/item?id=1203937>

~~~
mononcqc
Ah, my bad - hadn't seen that one and it (obviously) didn't get picked up as
the same link.

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abbetts
Its fine. Downloaded the pdf. Its straightforward. Good examples. The topic of
graphs is so interesting. Its more fun, as you read, to think about how this
can describe real world networks like facebook friends, traffic patterns on a
gmap, internet routers, world trade patterns.

~~~
roundsquare
As a note, its still being written. The later chapters are not even written at
all, they just have notes of topics to be covered.

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anatoly
I applaud the effort, yet deplore the writing. I looked at the first few pages
and was dismayed. This isn't a book I would recommend to anyone with no
knowledge of graph theory who needs to pick it up.

The authors make no effort to connect to someone who either doesn't have the
math background, or forgot it since they did their math courses in college X
years ago. Look at the very first sentences: they intimidate almost willfully.
Before we're ever told what a graph is, we're told that it's very hard to
define and there are "directed graphs, weighted graphs, multigraphs, simple
graphs and so on". Why? What possible benefit is there of saying this except
to intimidate? I don't yet know what a graph is - or probably I do intuitively
but not exactly. I'm not going to remember all these words!

Then "we start by calling a "graph" what some would call an "unweighted,
undirected graph w/o multiple edges" ". Again, why? What's wrong with saying
this five pages on, after you explain something about direction, multiple
edges, maybe weights? The tone seems almost hostile in its dryness.

Then the definition itself is a perfect specimen of a definition aimed solely
at a professional mathematician, who is almost never the intended audience of
this book (I assume). An ordered pair of sets? Why? Suppose that I remember
well what an ordered pair of sets is; if I'm not a mathematician, I almost
certainly don't have the intuition that it's just a shortcut way of specifying
"V and E". There's no important reason to define a graph as an ordered pair;
it's just a formalistic convention. You're not going to be writing out proofs
in ZFC about graphs. Even the Sage examples in the book don't follow the (V,E)
notation. Why not just say something like "a graph is defined by a set of
vertices V and a set of nodes E, where each node in E connects two vertices in
V together"? And immediately follow up with a simple example/picture? And
then, after the image is clear to the reader and they understand _what it is
that you want to model mathematically_ , then talk about formal ways of
representing it, and maybe, if you really want to use it, remind the reader
what a cartesian product is, and so on.

When you say "Elements of V are called _vertices_, or _nodes_, and elements of
E are called _edges_, or _arcs_", why not add "equivalently" after the "or"-s?
Again, someone who last read a formal definition of this kind X years ago - or
never - is not going to _immediately_ understand that you're just introducing
synonyms. They're gonna go "huh? so when is it vertices and when is it nodes?"
at least for a few seconds. Why do that?

In fact, I would say that any reader who's at home with the language and the
meaning of this definition will be a reader who definitely already knows what
an undirected graph is, formally. In other words, someone who needs this
definition will almost certainly have to struggle to understand it. This is
the opposite of what you want from a definition.

And all that - just on the first page!

~~~
mononcqc
I found myself having no problem reading it, knowing bits of set theory I had
taught myself beforehand, but I have to admit I would have been confused
otherwise.

Given the authors have the book open-sourced and that this looks like it's
still a draft, it might be a good idea to forward your criticism to the
authors. I'm sure they'd appreciate it.

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dusklight
Shouldn't this have been implemented as a wiki?

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gcb
finally. A book where i can change the style and tex it in a way i can just
scroll down on my cell phone screen. Instead of left-right for every damn
line.

Damn {pdf,ps}!

