edu.rit.numeric.plot
Class Axis

java.lang.Object
  edu.rit.numeric.plot.Axis

Direct Known Subclasses:

NumericalAxis

public abstract class Axis
extends Object

Class Axis is the abstract base class for an axis on a plot. It also provides static methods to help determine the scale for an axis.

Field Summary

static Paint	DEFAULT_PAINT The default axis paint (black).
static Stroke	DEFAULT_STROKE The default axis stroke (solid, width=1).
protected double	myLength Length of this axis on the display.
protected Paint	myPaint Paint for drawing this axis on the display.
protected Stroke	myStroke Stroke for drawing this axis on the display.

Constructor Summary

protected

Axis(double theLength, Stroke theStroke, Paint thePaint) Construct a new axis.

Method Summary

static double	autoscale(double max) Determine a pleasing scale for an axis.
abstract void	drawHorizontal(Graphics2D g2d) Draw this axis in the given graphics context starting at coordinates (0, 0) and moving horizontally to the right.
abstract void	drawVertical(Graphics2D g2d) Draw this axis in the given graphics context starting at coordinates (0, 0) and moving vertically up.
double	getLength() Returns the length of this axis on the display.
Paint	getPaint() Returns the paint for drawing this axis on the display.
Stroke	getStroke() Returns the stroke for drawing this axis on the display.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

DEFAULT_STROKE

public static final Stroke DEFAULT_STROKE

The default axis stroke (solid, width=1).

DEFAULT_PAINT

public static final Paint DEFAULT_PAINT

The default axis paint (black).

myLength

protected double myLength

Length of this axis on the display.

myStroke

protected Stroke myStroke

Stroke for drawing this axis on the display.

myPaint

protected Paint myPaint

Paint for drawing this axis on the display.

Constructor Detail

Axis

protected Axis(double theLength,
               Stroke theStroke,
               Paint thePaint)

Construct a new axis. The axis is drawn with the given length, stroke, and paint.

Parameters:

theLength - Length of this axis on the display.

theStroke - Stroke for drawing this axis on the display.

thePaint - Paint for drawing this axis on the display.

Throws:

NullPointerException - (unchecked exception) Thrown if theStroke is null or thePaint is null.

IllegalArgumentException - (unchecked exception) Thrown if theLength is less than or equal to 0.

Method Detail

getLength

public double getLength()

Returns the length of this axis on the display.

getStroke

public Stroke getStroke()

Returns the stroke for drawing this axis on the display.

getPaint

public Paint getPaint()

Returns the paint for drawing this axis on the display.

drawHorizontal

public abstract void drawHorizontal(Graphics2D g2d)

Draw this axis in the given graphics context starting at coordinates (0, 0) and moving horizontally to the right.

Parameters:

g2d - 2-D graphics context.

drawVertical

public abstract void drawVertical(Graphics2D g2d)

Draw this axis in the given graphics context starting at coordinates (0, 0) and moving vertically up.

Parameters:

g2d - 2-D graphics context.

autoscale

public static double autoscale(double max)

Determine a pleasing scale for an axis. The input, max, is the largest value to be displayed along the axis. The output is the smallest number of the form 1x10^k, 2x10^k, or 5x10^k, k an integer, that is greater than or equal to max. This can then be used as the maximum value for the axis.

Note: The autoscale() method works for negative inputs. If max < 0, then autoscale(max) = -autoscale(-max).

Note: autoscale(0) = 0.

Parameters:

max - Maximum value to be displayed along the axis.

Returns:

Maximum value for the axis.