NAO Class NADisc

Overview

An NADisc is the region

   Disc = { x | x in R^2, |x-c|<=1 }

It is very similar to the NABall, except that the radius is always 1, the Disc is always 2-dimensional, and the Disc has a boundary (the unit circle with the same center).

User's Guide

To use this class, you must include the header file

NAO/Disc.h

and link against library

libNAOBase.a

The following constructors are provided:

NADisc(xc ,yc );

Create a Unit Disc in the plane.

double xc ; X-coordinate of the center of the disc.

double yc ; Y-coordinate of the center of the disc.
NADisc();

Create an NADisc. (default constructor).

The following member functions are available in addition to those provided by the abstract interface NARegion:

NONE

Programmer's Guide

The NADisc stores the center of the Disc. The default origin is the point (0,0).

The test for inclusion in the Disc is simply:

  isitinChart((x,y))= (x-xc)*(x-xc)+(y-yc)*(y-yc) <= 1

The Disc, unlike the Ball, has a boundary. The boundary is a unit circle with the same center as the Disc. The boundary is implemented as a class private to the Disc, of type "DiscBoundary".

Example

To create a unit disc with center at 1,2:

#include<NAO/Disc.h>

NAManifold *disc=new NADisc(1.,2.);

See also the Disc example in the Examples document.

Related Classes and Subroutines

The parent of this class:

NARegion

Siblings of this class: