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
10 \section requirementsLEMON Hardware and software requirements
12 Hardware requirements ...
14 You will also need a C++ compiler. We mostly used the Gnu C++ Compiler (g++),
15 from version 3.0 upwards. We also checked the Intel C compiler
16 (icc). Unfortunately, Visual C++ compiler knows not enough to compile the
17 library, so if you are using Microsoft Windows, then try to compile under
22 -Hol fordul (Windows-os fordító nem fordítja, unix/linux alatt gcc hanyas verziója kell)
25 In this description we will suppose a linux environment and Gnu C Compiler.
27 \section downloadLEMON How to download LEMON
29 You can download LEMON from the LEMON web site:
30 http://lemon.cs.elte.hu/dowload.html
31 . There you will find the issued distributions
32 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.
36 \section installLEMON How to install LEMON
38 In order to install LEMON you have to do the following
40 Download the tarball (named <tt>lemon-x.y.z.tar.gz</tt> where \c x,\c y and \c z are
41 numbers indicating the version of the library: in our example we will have lemon-0.3.1) and issue the following commands:
44 tar xvzf lemon-0.3.1.tar.gz
48 make check (This is optional, but recomended. It runs a bunch of tests.)
52 These commands install LEMON under \c /usr/local (you will probably need \c root
53 privileges to be able to install to that directory). If you want to install it
54 to some other place, then pass the \c --prefix=DIR flag to \c ./configure. In
55 what follows we will assume that you were able to install to directory \c
56 /usr/local, otherwise some extra care is to be taken to use the library.
58 We briefly explain these commands below.
61 tar xvzf lemon-0.3.1.tar.gz
63 This command untars the <tt>tar.gz</tt> file into a directory named <tt> lemon-0.3.1</tt>.
73 Does some configuration (creates makefiles etc).
78 This command compiles the <tt> .cc</tt> files of the library package (the
79 implementation of non-template functions and classes and some test and demo
80 programs) and creates the very important <b> libemon.la </b> file. When
81 linking your program that uses LEMON it needs to access this file.
84 make check (This is optional, but recomended. It runs a bunch of tests.)
86 This is an optional step: it runs the test programs that we developed for
88 whether the library works properly on your platform.
93 This will copy the directory structure to its final destination (e.g. to \c
94 /usr/local) so that your system can access it.
96 \section helloworld My first program using LEMON
98 If you have installed LEMON on your system you
99 can paste the following code
100 segment into a file to have a first working program that uses library LEMON.
104 #include <lemon/list_graph.h>
106 using namespace lemon;
110 typedef ListGraph Graph;
111 typedef Graph::EdgeIt EdgeIt;
112 typedef Graph::NodeIt NodeIt;
116 for (int i = 0; i < 3; i++)
119 for (NodeIt i(g); i!=INVALID; ++i)
120 for (NodeIt j(g); j!=INVALID; ++j)
121 if (i != j) g.addEdge(i, j);
123 std::cout << "Nodes:";
124 for (NodeIt i(g); i!=INVALID; ++i)
125 std::cout << " " << g.id(i);
126 std::cout << std::endl;
128 std::cout << "Edges:";
129 for (EdgeIt i(g); i!=INVALID; ++i)
130 std::cout << " (" << g.id(g.source(i)) << "," << g.id(g.target(i)) << ")";
131 std::cout << std::endl;
135 First let us briefly explain how this program works.
137 ListGraph is one of LEMON's graph classes. It is based on linked lists,
138 therefore iterating throuh its edges and nodes is fast.
140 After some convenient typedefs we create a graph and add three nodes to it.
141 Then we add edges to it to form a complete graph.
143 Then we iterate through all nodes of the graph. We use a constructor of the
144 node iterator to initialize it to the first node. The operator++ is used to
145 step to the next node. Using operator++ on the iterator pointing to the last
146 node invalidates the iterator i.e. sets its value to
147 \ref lemon::INVALID "INVALID". This is what we exploit in the stop condition.
149 We can also iterate through all edges of the graph very similarly. The
151 \c source member functions can be used to access the endpoints of an edge.
153 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
154 successful then it is very easy to compile this program with the following
155 command (the argument <tt>-lemon</tt> tells the compiler that we are using the
156 installed library LEMON):
158 g++ hemon.cc -o hemon -lemon
161 As a result you will get the exacutable \c hemon in
162 this directory that you can run by the command
168 If everything has gone well then the previous code fragment prints out the following:
173 Edges: (0,2) (1,2) (0,1) (2,1) (1,0) (2,0)
178 If you want to see more features, go to the \ref quicktour "Quick Tour to
179 LEMON", if you want to see see some demo programs then go to our
180 \ref demoprograms "Demo Programs" page!