=head1 NAME
Math::Interpolator::Knot - x/y point for use in interpolation
=head1 SYNOPSIS
use Math::Interpolator::Knot;
$pt = Math::Interpolator::Knot->new($x, $y);
$x = $pt->x;
$y = $pt->y;
$role = $pt->role;
=head1 DESCRIPTION
An object of this type represents a single known point on a
one-dimensional curve. It is intended for use with C,
which will interpolate a curve between known points. These points are
known as "knots".
=cut
package Math::Interpolator::Knot;
{ use 5.006; }
use warnings;
use strict;
our $VERSION = "0.005";
=head1 CONSTRUCTOR
=over
=item Math::Interpolator::Knot->new(X, Y)
Creates and returns a new knot object with the specified x and y
coordinates.
=cut
sub new { bless({ x => $_[1], y => $_[2] }, $_[0]) }
=back
=head1 METHODS
=over
=item $pt->x
Returns the x coordinate of the knot.
=cut
sub x { $_[0]->{x} }
=item $pt->y
Returns the y coordinate of the knot.
=cut
sub y { $_[0]->{y} }
=item $pt->role
Returns the string "KNOT". This is used to distinguish knots from other
types of entity that could appear in an interpolator's point list.
=cut
sub role { "KNOT" }
=back
=head1 SUBCLASSING
The interpolator uses only this public interface, so it is acceptable to
substitute any other class that implements this interface. This may be
done by subclassing this class, or by reimplementing all three methods
independently. This is useful, for example, if the exact coordinates
are expensive to calculate and it is desired to perform lazy evaluation
with memoisation.
=head1 SEE ALSO
L,
L
=head1 AUTHOR
Andrew Main (Zefram)
=head1 COPYRIGHT
Copyright (C) 2006, 2007, 2009, 2010, 2012
Andrew Main (Zefram)
=head1 LICENSE
This module is free software; you can redistribute it and/or modify it
under the same terms as Perl itself.
=cut
1;