TestVector2.java

package org.iplantc.phyloviewer.shared.math;

import org.junit.Test;

import junit.framework.TestCase;

public class TestVector2 extends TestCase
{

	double delta = 10E-14;

	@Test
	public void testSubtract()
	{
		Vector2 v0 = new Vector2(1.0, 1.0);
		Vector2 v1 = new Vector2(0.5, 0.5);

		Vector2 answer = v0.subtract(v1);

		assertEquals(answer.getX(), 0.5, delta);
		assertEquals(answer.getY(), 0.5, delta);
	}

	@Test
	public void testAdd()
	{
		Vector2 v0 = new Vector2(1.0, 1.0);
		Vector2 v1 = new Vector2(0.5, 0.5);

		Vector2 answer = v0.add(v1);

		assertEquals(answer.getX(), 1.5, delta);
		assertEquals(answer.getY(), 1.5, delta);
	}

	@Test
	public void testRotate()
	{
		Vector2 v0 = new Vector2(1.0, 0.0);
		Vector2 answer = v0.rotate(Math.PI / 2.0);

		assertEquals(0.0, answer.getX(), delta);
		assertEquals(1.0, answer.getY(), delta);
	}

	@Test
	public void testDistance()
	{
		Vector2 v0 = new Vector2(0.0, 0.0);
		Vector2 v1 = new Vector2(1.0, 1.0);

		assertEquals(Math.sqrt(2.0), v0.distance(v1), delta);
		assertEquals(Math.sqrt(2.0), v1.distance(v0), delta);

		Vector2 v2 = new Vector2(2.0, 3.0);
		assertEquals(Math.sqrt(5.0), v1.distance(v2), delta);
		assertEquals(Math.sqrt(5.0), v2.distance(v1), delta);
	}

	@Test
	public void testDistanceSquared()
	{
		Vector2 v0 = new Vector2(0.0, 0.0);
		Vector2 v1 = new Vector2(1.0, 1.0);

		assertEquals(2.0, v0.distanceSquared(v1), delta);
		assertEquals(2.0, v1.distanceSquared(v0), delta);

		Vector2 v2 = new Vector2(2.0, 3.0);
		assertEquals(5.0, v1.distanceSquared(v2), delta);
		assertEquals(5.0, v2.distanceSquared(v1), delta);
	}

	@Test
	public void testDot()
	{
		Vector2 v0 = new Vector2(4, 2);
		Vector2 v1 = new Vector2(7, -3);

		assertEquals(22, v0.dot(v1), delta);
	}
}