source: lemon-0.x/doc/maps.dox @ 273:e9024dad7fc1

/*!

\page maps How to write maps

\section read-maps Readable Maps

It is quite easy to write your own readmap for the edges or nodes of a graph.

You can find some example below.

This simple map assigns \f$\pi\f$ to each edge.

\code
struct MyMap 
{
  typedef double ValueType;
  double operator[](Graph::EdgeIt e) const { return M_PI;}
};
\endcode


Here is a more complex example. It provides a length function which is obtained
from a base length function modified by a potential difference.
\todo Please improve on the english. 

\code
class MyLengthMap 
{
  const Graph::EdgeMap &ol;
  const Graph::NodeMap &pot;
  
public:
  typedef double ValueType;

  double operator[](Graph::EdgeIt e) const {
    return ol.get(e)-pot.get(v)-pot.get(u);
  }
  
  MyComplexMap(const Graph::EdgeMap &o,const Graph::NodeMap &p) :
    ol(o), pot(p);
};
\endcode

\todo Don't we need \e to \e require a 'typedef xxx KeyType' tag, as well?
*/