File format of branching vector files
=====================================

Every branching vector file, both in ascii and binary format,
contains a list of pairs of branching vectors.  Here, the first
vector represents the mirrors branch, the second represents
the satellites branch, in both cases when branching on a
node v of maximal degree.

Each branching vector is a 16-tuple
(b_1, b_2, ..., b_8, b_1', b_2', ..., b_8').

The first 8 numbers represent the "no", branch, (i.e., v
is not part of the independet set), the next 8 numbers
represent the "yes" branch.

The meaning of b_1, ..., b_8 (and, accordingly, b_1', ..., b_8')
is as follows:
b_1: 			degree of v (here, 4 in all vectors)
b_2:			number of anonymous edges removed
b_i, 3 <= i <= 8:	number of nodes of degree i removed (positive)
			or created (negative)

In the ascii version, each pair of branching vectors is on a seperate line.
The pairs are divided by ';;', either component is marked by '|',
and each number is seperated by ',' and white space.

In the binary version, each pair is represented by 32 byte,
16 byte per branching vector, each byte representing a number
b_i as an "signed char" (i.e., 8bit signed integers).


Examples:
=========
Consider the following pair of branching vectors in ascii representation:
4 0 0 10 0 0 0 0 | 4 0 1 10 -1 0 0 0 ;; 4 2 0 11 0 0 0 0 | 4 0 -3 10 -1 0 0 0
^========== mirror branch =========^    ^========= satellite branch ========^

Mirror branch:
  "no":  10 nodes of degree 4 are gained,
  "yes": 10 nodes of degree 4 are gained, one node of degree 3, but
  	a node of degree 5 is created
Satellites branch:
  "no":  11 nodes of degree 4 are gained, two anonymous edges are gained
  "yes": 10 nodes of degree 4 are gained, but three nodes of
  	degree three and one node of degree 5 are created


You can view the branching vector binary files with the standard
od(1) UNIX-tool by invoking it as 'od -A d -v -t d1 <filename>'
(with byte offset) or 'od -A n -v -t d1 <filename>' (without):
Example:

$ bzcat vectors-4.bz2 | od -A n -v -t d1 | head
    4    0    4    8    0    0    0    0    4    0    0    5    0    0    0    0
    4    0    4    8    0    0    0    0    4    0    0    5    0    0    0    0
    4    0    2    9    0    0    0    0    4    0    0    5    0    0    0    0
    4    0    2    9    0    0    0    0    4    0    0    5    0    0    0    0
    4    0    4    8    0    0    0    0    4    2    4    8    0    0    0    0
    4    0    4    8    0    0    0    0    4    2    4    8    0    0    0    0
    4    0    2    9    0    0    0    0    4    2    2    9    0    0    0    0
    4    0    2    9    0    0    0    0    4    2    2    9    0    0    0    0
    4    0    4    8    0    0    0    0    4    2    4    8    0    0    0    0
    4    0    4    8    0    0    0    0    4    2    4    8    0    0    0    0

This corresponds to the ascii file as follows:
$ bzcat vectors-4.ascii.bz2 | head -n 5
4 0 4 8 0 0 0 0 | 4 0 0 5 0 0 0 0 ;; 4 0 4 8 0 0 0 0 | 4 0 0 5 0 0 0 0
4 0 2 9 0 0 0 0 | 4 0 0 5 0 0 0 0 ;; 4 0 2 9 0 0 0 0 | 4 0 0 5 0 0 0 0
4 0 4 8 0 0 0 0 | 4 2 4 8 0 0 0 0 ;; 4 0 4 8 0 0 0 0 | 4 2 4 8 0 0 0 0
4 0 2 9 0 0 0 0 | 4 2 2 9 0 0 0 0 ;; 4 0 2 9 0 0 0 0 | 4 2 2 9 0 0 0 0
4 0 4 8 0 0 0 0 | 4 2 4 8 0 0 0 0 ;; 4 0 4 8 0 0 0 0 | 4 2 4 8 0 0 0 0