2 \page getstart How to start using LEMON
4 In this page we detail how to start using LEMON, from downloading it to
5 your computer, through the steps of installation to showing a simple
6 "Hello World" type program that already uses LEMON. We assume that you have a
7 basic knowledge of your operating system and \c C++ or \c C
8 programming language. If anything is not
9 clear write to our FAQ.
11 \todo Is this FAQ thing a good idea here? Is there such a thing? If
12 twice YES then a link comes here.
14 \section requirementsLEMON Hardware and software requirements
16 Hardware requirements ...
18 You will also need a C++ compiler. We mostly used the Gnu C++ Compiler (g++),
19 from version 3.0 upwards. We also checked the Intel C compiler
20 (icc). Unfortunately, Visual C++ compiler knows not enough to compile the
21 library, so if you are using Microsoft Windows, then try to compile under
26 -Hol fordul (Windows-os fordító nem fordítja, unix/linux alatt gcc hanyas verziója kell)
29 In this description we will suppose a linux environment and Gnu C Compiler.
31 \section downloadLEMON How to download LEMON
33 You can download LEMON from the LEMON web site:
34 http://lemon.cs.elte.hu
35 by following the download link. There you will find the issued distributions
36 in form of <tt> .tar.gz </tt> files. If you want a developer version (for example you want to contribute in developing the library LEMON) then you might want to use our Subversion repository. This case is not detailed here, so from now on we suppose that you downloaded a tar.gz file.
40 \section installLEMON How to install LEMON
42 In order to install LEMON you have to do the following
44 Download the tarball (named <tt>lemon-x.y.z.tar.gz</tt> where \c x,\c y and \c z are
45 numbers indicating the version of the library: in our example we will have lemon-0.3.1) and issue the following commands:
48 tar xvzf lemon-0.3.1.tar.gz
52 make check (This is optional, but recomended. It runs a bunch of tests.)
56 These commands install LEMON under \c /usr/local (you will probably need \c root
57 privileges to be able to install to that directory). If you want to install it
58 to some other place, then pass the \c --prefix=DIR flag to \c ./configure. In
59 what follows we will assume that you were able to install to directory \c
60 /usr/local, otherwise some extra care is to be taken to use the library.
62 We briefly explain these commands below.
65 tar xvzf lemon-0.3.1.tar.gz
67 This command untars the <tt>tar.gz</tt> file into a directory named <tt> lemon-0.3.1</tt>.
77 Does some configuration (creates makefiles etc).
82 This command compiles the <tt> .cc</tt> files of the library package (the
83 implementation of non-template functions and classes and some test and demo
84 programs) and creates the very important <b> libemon.la </b> file. When
85 linking your program that uses LEMON it needs to access this file.
88 make check (This is optional, but recomended. It runs a bunch of tests.)
90 This is an optional step: it runs the test programs that we developed for
92 whether the library works properly on your platform.
97 This will copy the directory structure to its final destination (e.g. to \c
98 /usr/local) so that your system can access it.
100 \section helloworld My first program using LEMON
102 If you have installed LEMON on your system you
103 can paste the following code
104 segment into a file to have a first working program that uses library LEMON.
108 #include <lemon/list_graph.h>
110 using namespace lemon;
114 typedef ListGraph Graph;
115 typedef Graph::EdgeIt EdgeIt;
116 typedef Graph::NodeIt NodeIt;
120 for (int i = 0; i < 3; i++)
123 for (NodeIt i(g); i!=INVALID; ++i)
124 for (NodeIt j(g); j!=INVALID; ++j)
125 if (i != j) g.addEdge(i, j);
127 std::cout << "Nodes:";
128 for (NodeIt i(g); i!=INVALID; ++i)
129 std::cout << " " << g.id(i);
130 std::cout << std::endl;
132 std::cout << "Edges:";
133 for (EdgeIt i(g); i!=INVALID; ++i)
134 std::cout << " (" << g.id(g.source(i)) << "," << g.id(g.target(i)) << ")";
135 std::cout << std::endl;
139 First let us briefly explain how this program works.
141 ListGraph is one of LEMON's graph classes. It is based on linked lists,
142 therefore iterating throuh its edges and nodes is fast.
144 After some convenient typedefs we create a graph and add three nodes to it.
145 Then we add edges to it to form a complete graph.
147 Then we iterate through all nodes of the graph. We use a constructor of the
148 node iterator to initialize it to the first node. The operator++ is used to
149 step to the next node. Using operator++ on the iterator pointing to the last
150 node invalidates the iterator i.e. sets its value to
151 \ref lemon::INVALID "INVALID". This is what we exploit in the stop condition.
153 We can also iterate through all edges of the graph very similarly. The
155 \c source member functions can be used to access the endpoints of an edge.
157 If you have saved the preceding code into a file named, say, \c hemon.cc and your installation of LEMON into directory \c /usr/local was
158 successful then it is very easy to compile this program with the following
159 command (the argument <tt>-lemon</tt> tells the compiler that we are using the
160 installed library LEMON):
162 g++ hemon.cc -o hemon -lemon
165 As a result you will get the exacutable \c hemon in
166 this directory that you can run by the command
172 If everything has gone well then the previous code fragment prints out the following:
177 Edges: (0,2) (1,2) (0,1) (2,1) (1,0) (2,0)
182 If you want to see more features, go to the \ref quicktour "Quick Tour to
183 LEMON", if you want to see see some demo programs then go to our
184 \ref demoprograms "Demo Programs" page!