/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.commons.math4.util;
import java.math.BigDecimal;
import java.math.BigInteger;
import java.math.MathContext;
import org.apache.commons.math4.TestUtils;
import org.apache.commons.math4.exception.MathArithmeticException;
import org.apache.commons.math4.util.BigReal;
import org.apache.commons.math4.util.FastMath;
import org.junit.Assert;
import org.junit.Test;
public class BigRealTest {
@Test
public void testConstructor() {
Assert.assertEquals(1.625,
new BigReal(new BigDecimal("1.625")).doubleValue(),
1.0e-15);
Assert.assertEquals(-5.0,
new BigReal(new BigInteger("-5")).doubleValue(),
1.0e-15);
Assert.assertEquals(-5.0, new BigReal(new BigInteger("-5"),
MathContext.DECIMAL64)
.doubleValue(), 1.0e-15);
Assert
.assertEquals(0.125,
new BigReal(new BigInteger("125"), 3).doubleValue(),
1.0e-15);
Assert.assertEquals(0.125, new BigReal(new BigInteger("125"), 3,
MathContext.DECIMAL64)
.doubleValue(), 1.0e-15);
Assert.assertEquals(1.625, new BigReal(new char[] {
'1', '.', '6', '2', '5'
}).doubleValue(), 1.0e-15);
Assert.assertEquals(1.625, new BigReal(new char[] {
'A', 'A', '1', '.', '6', '2', '5', '9'
}, 2, 5).doubleValue(), 1.0e-15);
Assert.assertEquals(1.625, new BigReal(new char[] {
'A', 'A', '1', '.', '6', '2', '5', '9'
}, 2, 5, MathContext.DECIMAL64).doubleValue(), 1.0e-15);
Assert.assertEquals(1.625, new BigReal(new char[] {
'1', '.', '6', '2', '5'
}, MathContext.DECIMAL64).doubleValue(), 1.0e-15);
Assert.assertEquals(1.625, new BigReal(1.625).doubleValue(), 1.0e-15);
Assert.assertEquals(1.625, new BigReal(1.625, MathContext.DECIMAL64)
.doubleValue(), 1.0e-15);
Assert.assertEquals(-5.0, new BigReal(-5).doubleValue(), 1.0e-15);
Assert.assertEquals(-5.0, new BigReal(-5, MathContext.DECIMAL64)
.doubleValue(), 1.0e-15);
Assert.assertEquals(-5.0, new BigReal(-5l).doubleValue(), 1.0e-15);
Assert.assertEquals(-5.0, new BigReal(-5l, MathContext.DECIMAL64)
.doubleValue(), 1.0e-15);
Assert.assertEquals(1.625, new BigReal("1.625").doubleValue(), 1.0e-15);
Assert.assertEquals(1.625, new BigReal("1.625", MathContext.DECIMAL64)
.doubleValue(), 1.0e-15);
}
@Test
public void testCompareTo() {
BigReal first = new BigReal(1.0 / 2.0);
BigReal second = new BigReal(1.0 / 3.0);
BigReal third = new BigReal(1.0 / 2.0);
Assert.assertEquals(0, first.compareTo(first));
Assert.assertEquals(0, first.compareTo(third));
Assert.assertEquals(1, first.compareTo(second));
Assert.assertEquals(-1, second.compareTo(first));
}
@Test
public void testAdd() {
BigReal a = new BigReal("1.2345678");
BigReal b = new BigReal("8.7654321");
Assert.assertEquals(9.9999999, a.add(b).doubleValue(), 1.0e-15);
}
@Test
public void testSubtract() {
BigReal a = new BigReal("1.2345678");
BigReal b = new BigReal("8.7654321");
Assert.assertEquals(-7.5308643, a.subtract(b).doubleValue(), 1.0e-15);
}
@Test
public void testNegate() {
BigReal a = new BigReal("1.2345678");
BigReal zero = new BigReal("0.0000000");
Assert.assertEquals(a.negate().add(a), zero);
Assert.assertEquals(a.add(a.negate()), zero);
Assert.assertEquals(zero, zero.negate());
}
@Test
public void testDivide() {
BigReal a = new BigReal("1.0000000000");
BigReal b = new BigReal("0.0009765625");
Assert.assertEquals(1024.0, a.divide(b).doubleValue(), 1.0e-15);
}
@Test(expected = MathArithmeticException.class)
public void testDivisionByZero() {
final BigReal a = BigReal.ONE;
final BigReal b = BigReal.ZERO;
a.divide(b);
}
@Test
public void testReciprocal() {
BigReal a = new BigReal("1.2345678");
double eps = FastMath.pow(10., -a.getScale());
BigReal one = new BigReal("1.0000000");
BigReal b = a.reciprocal();
BigReal r = one.subtract(a.multiply(b));
Assert.assertTrue(FastMath.abs(r.doubleValue()) <= eps);
r = one.subtract(b.multiply(a));
Assert.assertTrue(FastMath.abs(r.doubleValue()) <= eps);
}
@Test(expected = MathArithmeticException.class)
public void testReciprocalOfZero() {
BigReal.ZERO.reciprocal();
}
@Test
public void testMultiply() {
BigReal a = new BigReal("1024.0");
BigReal b = new BigReal("0.0009765625");
Assert.assertEquals(1.0, a.multiply(b).doubleValue(), 1.0e-15);
int n = 1024;
Assert.assertEquals(1.0, b.multiply(n).doubleValue(), 1.0e-15);
}
@Test
public void testDoubleValue() {
Assert.assertEquals(0.5, new BigReal(0.5).doubleValue(), 1.0e-15);
}
@Test
public void testBigDecimalValue() {
BigDecimal pi = new BigDecimal(
"3.1415926535897932384626433832795028841971693993751");
Assert.assertEquals(pi, new BigReal(pi).bigDecimalValue());
Assert.assertEquals(new BigDecimal(0.5),
new BigReal(1.0 / 2.0).bigDecimalValue());
}
@Test
public void testEqualsAndHashCode() {
BigReal zero = new BigReal(0.0);
BigReal nullReal = null;
Assert.assertTrue(zero.equals(zero));
Assert.assertFalse(zero.equals(nullReal));
Assert.assertFalse(zero.equals(Double.valueOf(0)));
BigReal zero2 = new BigReal(0.0);
Assert.assertTrue(zero.equals(zero2));
Assert.assertEquals(zero.hashCode(), zero2.hashCode());
BigReal one = new BigReal(1.0);
Assert.assertFalse((one.equals(zero) || zero.equals(one)));
Assert.assertTrue(one.equals(BigReal.ONE));
}
@Test
public void testSerial() {
BigReal[] Reals = {
new BigReal(3.0), BigReal.ONE, BigReal.ZERO, new BigReal(17),
new BigReal(FastMath.PI), new BigReal(-2.5)
};
for (BigReal Real : Reals) {
Assert.assertEquals(Real, TestUtils.serializeAndRecover(Real));
}
}
}