/*
?*?Created?on?05/05/2005
?*
?*?TODO?To?change?the?template?for?this?generated?file?go?to
?*?Window?-?Preferences?-?Java?-?Code?style?-?Code?Templates
?*/

/**
?*?
?*?TODO?Short?description?of?the?class
?*?
?*?@author?Thiago?Bassani（tbassani@ppgia.pucpr.br）???
?*/
public?class?MathTest?{

	public?static?void?main（String[]?args）?{
		System.out.println（vectorOrientation（0.50））;
		System.out.println（vectorOrientation（10.5））;
		System.out.println（vectorOrientation（0.51））;
		System.out.println（vectorOrientation（00.5））;
	}
	/**
	?*?@return?1??DOWN
	?*?@return?2??UP
	?*?@return?3??LEFT
	?*?@return?4??RIGHT
	?*/
	public?static?int?vectorOrientation（double?xdouble?y）{
		double?centerX?=?0.5;
		double?centerY?=?0.5;
		if（cosVectors（x-centerXy-centerYcenterX0）?>=?0.701）
			return?4;//RIGHT
		if（cosVectors（x-centerXy-centerYcenterX0）?<=?-0.701）
			return?3;//LEFT
		if（cosVectors（x-centerXy-centerY0centerY）?>=?0.701）
			return?2;//UP
		return?1;//DOWN
	}

	public?static?double?cosVectors（double?x1double?y1double?x2double?y2）{
		double?num?=?x1*x2?+?y1*y2;
		double?den?=?Math.sqrt（x1*x1+y1*y1）*Math.sqrt（x2*x2+y2*y2）;
		double?ret?=?num/den;
		if（Double.isNaN（ret））
			return?0;
		return?ret;
	}
}

?屬性????????????大小?????日期????時間???名稱
-----------?---------??----------?-----??----
?????文件????????1201??2005-05-13?09:44??MathTest.class
?????文件????????1272??2005-05-05?01:09??MathTest.java
?????文件????????1675??2005-05-13?09:44??RogalPlayer.class
?????文件????????2778??2005-05-05?10:23??RogalPlayer.java
?????文件?????????330??2005-05-04?09:31??.settings\org.eclipse.jdt.core.prefs
?????文件????????1862??2005-05-09?08:56??doc\allclasses-frame.html
?????文件????????1682??2005-05-09?08:56??doc\allclasses-noframe.html
?????文件????????7234??2005-05-09?08:56??doc\constant-values.html
?????文件????????4992??2005-05-09?08:56??doc\deprecated-list.html
?????文件???????34459??2005-05-09?08:56??doc\edu\pucpr\engcomp\dotbox\Box.html
?????文件???????23897??2005-05-09?08:56??doc\edu\pucpr\engcomp\dotbox\class-use\Box.html
?????文件????????5831??2005-05-09?08:56??doc\edu\pucpr\engcomp\dotbox\class-use\DotsAndBoxesGame.html
?????文件???????17546??2005-05-09?08:56??doc\edu\pucpr\engcomp\dotbox\class-use\IPlayer.html
?????文件???????11412??2005-05-09?08:56??doc\edu\pucpr\engcomp\dotbox\class-use\PlayerAction.html
?????文件???????22165??2005-05-09?08:56??doc\edu\pucpr\engcomp\dotbox\DotsAndBoxesGame.html
?????文件????????5890??2005-05-09?08:56??doc\edu\pucpr\engcomp\dotbox\dummy\class-use\DummyPlayer.html
?????文件???????13940??2005-05-09?08:56??doc\edu\pucpr\engcomp\dotbox\dummy\DummyPlayer.html
?????文件?????????987??2005-05-09?08:56??doc\edu\pucpr\engcomp\dotbox\dummy\package-frame.html
?????文件????????6309??2005-05-09?08:56??doc\edu\pucpr\engcomp\dotbox\dummy\package-summary.html
?????文件????????6293??2005-05-09?08:56??doc\edu\pucpr\engcomp\dotbox\dummy\package-tree.html
?????文件????????5521??2005-05-09?08:56??doc\edu\pucpr\engcomp\dotbox\dummy\package-use.html
?????文件????????5906??2005-05-09?08:56??doc\edu\pucpr\engcomp\dotbox\expert\class-use\ExpertPlayer.html
?????文件???????14956??2005-05-09?08:56??doc\edu\pucpr\engcomp\dotbox\expert\ExpertPlayer.html
?????文件?????????994??2005-05-09?08:56??doc\edu\pucpr\engcomp\dotbox\expert\package-frame.html
?????文件????????6325??2005-05-09?08:56??doc\edu\pucpr\engcomp\dotbox\expert\package-summary.html
?????文件????????6309??2005-05-09?08:56??doc\edu\pucpr\engcomp\dotbox\expert\package-tree.html
?????文件????????5525??2005-05-09?08:56??doc\edu\pucpr\engcomp\dotbox\expert\package-use.html
?????文件???????10274??2005-05-09?08:56??doc\edu\pucpr\engcomp\dotbox\IPlayer.html
?????文件????????1477??2005-05-09?08:56??doc\edu\pucpr\engcomp\dotbox\package-frame.html
?????文件????????7161??2005-05-09?08:56??doc\edu\pucpr\engcomp\dotbox\package-summary.html
?????文件????????6586??2005-05-09?08:56??doc\edu\pucpr\engcomp\dotbox\package-tree.html
............此處省略78個文件信息