1.1 --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     1.2 +++ b/doc/lgf.dox	Sat May 17 06:30:02 2008 +0100
     1.3 @@ -0,0 +1,96 @@
     1.4 +/* -*- C++ -*-
     1.5 + *
     1.6 + * This file is a part of LEMON, a generic C++ optimization library
     1.7 + *
     1.8 + * Copyright (C) 2003-2008
     1.9 + * Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport
    1.10 + * (Egervary Research Group on Combinatorial Optimization, EGRES).
    1.11 + *
    1.12 + * Permission to use, modify and distribute this software is granted
    1.13 + * provided that this copyright notice appears in all copies. For
    1.14 + * precise terms see the accompanying LICENSE file.
    1.15 + *
    1.16 + * This software is provided "AS IS" with no warranty of any kind,
    1.17 + * express or implied, and with no claim as to its suitability for any
    1.18 + * purpose.
    1.19 + *
    1.20 + */
    1.21 +
    1.22 +namespace lemon {
    1.23 +/*!
    1.24 +
    1.25 +
    1.26 +
    1.27 +\page lgf-format Lemon Graph Format (LGF)
    1.28 +
    1.29 +The \e LGF is a <em>column oriented</em>
    1.30 +file format for storing graphs and associated data like
    1.31 +node and edge maps.
    1.32 +
    1.33 +Each line with \c '#' first non-whitespace
    1.34 +character is considered as a comment line.
    1.35 +
    1.36 +Otherwise the file consists of sections starting with
    1.37 +a header line. The header lines starts with an \c '@' character followed by the
    1.38 +type of section. The standard section types are \c \@nodes, \c
    1.39 +\@arcs and \c \@edges
    1.40 +and \@attributes. Each header line may also have an optional
    1.41 +\e name, which can be use to distinguish the sections of the same
    1.42 +type.
    1.43 +
    1.44 +The standard sections are column oriented, each line consists of
    1.45 +<em>token</em>s separated by whitespaces. A token can be \e plain or
    1.46 +\e quoted. A plain token is just a sequence of non-whitespace characters,
    1.47 +while a quoted token is a
    1.48 +character sequence surrounded by double quotes, and it can also
    1.49 +contain whitespaces and escape sequences. 
    1.50 +
    1.51 +The \c \@nodes section describes a set of nodes and associated
    1.52 +maps. The first is a header line, it columns are the names of the
    1.53 +maps appearing in the following lines.
    1.54 +One of the maps must be called \c
    1.55 +"label", which plays special role in the file.
    1.56 +The following
    1.57 +non-empty lines until the next section describes nodes of the
    1.58 +graph. Each line contains the values of the node maps
    1.59 +associated to the current node.
    1.60 +
    1.61 +\code
    1.62 + @nodes
    1.63 + label   coordinates size    title
    1.64 + 1       (10,20)     10      "First node"
    1.65 + 2       (80,80)     8       "Second node"
    1.66 + 3       (40,10)     10      "Third node"
    1.67 +\endcode
    1.68 +
    1.69 +The \c \@arcs section is very similar to the \c \@nodes section,
    1.70 +it again starts with a header line describing the names of the arc,
    1.71 +but the \c "label" map is not obligatory here. The following lines
    1.72 +describe the arcs. The first two tokens of each line are
    1.73 +the source and the target node of the arc, respectively, then come the map
    1.74 +values. The source and target tokens must be node labels.
    1.75 +
    1.76 +\code
    1.77 + @arcs
    1.78 + 	      capacity
    1.79 + 1   2   16
    1.80 + 1   3   12
    1.81 + 2   3   18
    1.82 +\endcode
    1.83 +
    1.84 +The \c \@edges is just a synonym of \c \@arcs.
    1.85 +
    1.86 +The \c \@attributes section contains key-value pairs, each line
    1.87 +consists of two tokens, an attribute name, and then an attribute value.
    1.88 +
    1.89 +\code
    1.90 + @attributes
    1.91 + source 1
    1.92 + target 3
    1.93 + caption "LEMON test digraph"
    1.94 +\endcode
    1.95 +
    1.96 +*/
    1.97 +}
    1.98 +
    1.99 +//  LocalWords:  whitespace whitespaces