Version 5.0 The LEDA User Manual

at segment s(const segment& s1 , int prec = rat point :: default precision);
introduces a variable s of type rat segment. s is initialized
to the segment obtained by approximating the two defining
points of s 1 .
4. Operations
segment s.to float( ) returns a floating point approximation of s.
void s.normalize( ) simplifies the homogenous representation by calling
source( ).normalize( ) and target( ).normlize( ).
rat point s.start( ) returns the source point of s.
rat point s.end( ) returns the target point of s.
rat segment s.reversal( ) returns the segment (target( ), source( )).
rational s.xcoord1( ) returns the x-coordinate of the source point of s.
rational s.xcoord2( ) returns the x-coordinate of the target point of s.
rational s.ycoord1( ) returns the y-coordinate of the source point of s.
rational s.ycoord2( ) returns the y-coordinate of the target point of s.
double s.xcoord1D( ) returns a double precision approximation of s.xcoord1 ( ).
double s.xcoord2D( ) returns a double precision approximation of s.xcoord2 ( ).
double s.ycoord1D( ) returns a double precision approximation of s.ycoord1 ( ).
double s.ycoord2D( ) returns a double precision approximation of s.ycoord2 ( ).
integer s.X1( ) returns the first homogeneous coordinate of the source
point of s.
integer s.X2( ) returns the first homogeneous coordinate of the target
point of s.
integer s.Y1( ) returns the second homogeneous coordinate of the source
point of s.
integer s.Y2( ) returns the second homogeneous coordinate of the target
point of s.
integer s.W1( ) returns the third homogeneous coordinate of the source
point of s.