Re: BGL wrapper for SGB

From: Andreas Scherer (as_at_[hidden])
Date: 2000-10-03 13:58:19

--- In boost_at_[hidden], "Andreas Scherer" <as_at_m...> wrote:
> Only if my assumption is correct that the PROTOTYPES really are
> sufficient for <gb_graph.h> to be #included safely in
> <stanford_graph.hpp> in an "extern "C"" group.

Indeed it is!!!

I found that <stanford_graph.hpp> is used exclusively in the
"miles_span" example program.  So, I #included the patched SGB header
files <gb_graph.h>, <gb_miles.h>, and <gb_save.h> instead of the
repeated SGB stuff in <stanford_graph.hpp> and recompiled
"miles_span.cpp" with the updated headers and linked it with the newly
compiled SGB library.  Alas, this approach works fine.

But here are two remarks: Firstly, <stanford_graph.hpp> repeats only
the stuff needed in "miles_span.cpp", so it is _not_ a general
interface for other types of SGB graphs.  Why declare the "miles"
graph in <stanford_graph.hpp>, but non other generating function?

Secondly, BGL's version of "miles_span" reports the minimum spanning
tree of length 8075, while SGB's version of "miles_span" reports a
length of 14467 (and this value also is "in the book"), although both
programs claim to operate on the same graph. I believe, one version
must be wrong!  (And guess which...)

Andreas