Version 5.0 The LEDA User Manual

integer s.W2( ) returns the third homogeneous coordinate of the target
point of s.
double s.XD1( ) returns a floating point approximation of s.X1 ( ).
double s.XD2( ) returns a floating point approximation of s.X2 ( ).
double s.YD1( ) returns a floating point approximation of s.Y1 ( ).
double s.YD2( ) returns a floating point approximation of s.Y2 ( ).
double s.WD1( ) returns a floating point approximation of s.W1 ( ).
double s.WD2( ) returns a floating point approximation of s.W2 ( ).
integer s.dx( ) returns the normalized x-difference X2 · W 1 − X1 · W 2 of
s.
integer s.dy( ) returns the normalized y-difference Y 2 · W 1 − Y 1 · W 2 of
s.
double s.dxD( ) returns a floating point approximation of s.dx( ).
double s.dyD( ) returns a floating point approximation of s.dy( ).
bool s.is trivial( ) returns true if s is trivial.
bool s.is vertical( ) returns true if s is vertical.
Precondition: s is non-trivial.
bool s.is horizontal( ) returns true if s is horizontal.
Precondition: s is non-trivial.
rational s.slope( ) returns the slope of s.
Precondition: s is not vertical.
int s.cmp slope(const rat segment& s1 )
int s.orientation(const rat point& p)
rational s.x proj(rational y)
rational s.y proj(rational x)
compares the slopes of s and s 1 .
Precondition: s and s 1 are non-trivial.
computes orientation(a, b, p) (see below), where a ≠ b and
a and b appear in this order on segment s.
returns p.xcoord(), where p ∈ line(s) with p.ycoord() = y.
Precondition: s is not horizontal.
returns p.ycoord(), where p ∈ line(s) with p.xcoord() = x.
Precondition: s is not vertical.