alvinalexander.com | career | drupal | java | mac | mysql | perl | scala | uml | unix  

Commons Math example source code file (BigFractionTest.java)

This example Commons Math source code file (BigFractionTest.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" TM.

Java - Commons Math tags/keywords

arithmeticexception, arithmeticexception, bigdecimal, bigfraction, bigfraction, bigfractiontest, biginteger, convergenceexception, convergenceexception, exception, fractionconversionexception, math, nullpointerexception, nullpointerexception, testcase

The Commons Math BigFractionTest.java source code

/*
 * 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.math.fraction;

import java.math.BigDecimal;
import java.math.BigInteger;

import org.apache.commons.math.ConvergenceException;
import org.apache.commons.math.TestUtils;

import junit.framework.TestCase;

public class BigFractionTest extends TestCase {

    private void assertFraction(int expectedNumerator, int expectedDenominator, BigFraction actual) {
        assertEquals(expectedNumerator, actual.getNumeratorAsInt());
        assertEquals(expectedDenominator, actual.getDenominatorAsInt());
    }

    private void assertFraction(long expectedNumerator, long expectedDenominator, BigFraction actual) {
        assertEquals(expectedNumerator, actual.getNumeratorAsLong());
        assertEquals(expectedDenominator, actual.getDenominatorAsLong());
    }

    public void testConstructor() {
        assertFraction(0, 1, new BigFraction(0, 1));
        assertFraction(0, 1, new BigFraction(0l, 2l));
        assertFraction(0, 1, new BigFraction(0, -1));
        assertFraction(1, 2, new BigFraction(1, 2));
        assertFraction(1, 2, new BigFraction(2, 4));
        assertFraction(-1, 2, new BigFraction(-1, 2));
        assertFraction(-1, 2, new BigFraction(1, -2));
        assertFraction(-1, 2, new BigFraction(-2, 4));
        assertFraction(-1, 2, new BigFraction(2, -4));
        assertFraction(11, 1, new BigFraction(11));
        assertFraction(11, 1, new BigFraction(11l));
        assertFraction(11, 1, new BigFraction(new BigInteger("11")));

        try {
            assertFraction(0, 1, new BigFraction(0.00000000000001, 1.0e-5, 100));
            assertFraction(2, 5, new BigFraction(0.40000000000001, 1.0e-5, 100));
            assertFraction(15, 1, new BigFraction(15.0000000000001, 1.0e-5, 100));
        } catch (ConvergenceException ex) {
            fail(ex.getMessage());
        }
        assertEquals(0.00000000000001, new BigFraction(0.00000000000001).doubleValue(), 0.0);
        assertEquals(0.40000000000001, new BigFraction(0.40000000000001).doubleValue(), 0.0);
        assertEquals(15.0000000000001, new BigFraction(15.0000000000001).doubleValue(), 0.0);
        assertFraction(3602879701896487l, 9007199254740992l, new BigFraction(0.40000000000001));
        assertFraction(1055531162664967l, 70368744177664l, new BigFraction(15.0000000000001));
        try {
            new BigFraction(null, BigInteger.ONE);
        } catch (NullPointerException npe) {
            // expected
        }
        try {
            new BigFraction(BigInteger.ONE, null);
        } catch (NullPointerException npe) {
            // expected
        }
        try {
            new BigFraction(BigInteger.ONE, BigInteger.ZERO);
        } catch (ArithmeticException npe) {
            // expected
        }
        try {
            new BigFraction(2.0 * Integer.MAX_VALUE, 1.0e-5, 100000);
        } catch (FractionConversionException fce) {
            // expected
        }
    }

    public void testGoldenRatio() {
        try {
            // the golden ratio is notoriously a difficult number for continuous
            // fraction
            new BigFraction((1 + Math.sqrt(5)) / 2, 1.0e-12, 25);
            fail("an exception should have been thrown");
        } catch (ConvergenceException ce) {
            // expected behavior
        } catch (Exception e) {
            fail("wrong exception caught");
        }
    }

    // MATH-179
    public void testDoubleConstructor() throws ConvergenceException {
        assertFraction(1, 2, new BigFraction((double) 1 / (double) 2, 1.0e-5, 100));
        assertFraction(1, 3, new BigFraction((double) 1 / (double) 3, 1.0e-5, 100));
        assertFraction(2, 3, new BigFraction((double) 2 / (double) 3, 1.0e-5, 100));
        assertFraction(1, 4, new BigFraction((double) 1 / (double) 4, 1.0e-5, 100));
        assertFraction(3, 4, new BigFraction((double) 3 / (double) 4, 1.0e-5, 100));
        assertFraction(1, 5, new BigFraction((double) 1 / (double) 5, 1.0e-5, 100));
        assertFraction(2, 5, new BigFraction((double) 2 / (double) 5, 1.0e-5, 100));
        assertFraction(3, 5, new BigFraction((double) 3 / (double) 5, 1.0e-5, 100));
        assertFraction(4, 5, new BigFraction((double) 4 / (double) 5, 1.0e-5, 100));
        assertFraction(1, 6, new BigFraction((double) 1 / (double) 6, 1.0e-5, 100));
        assertFraction(5, 6, new BigFraction((double) 5 / (double) 6, 1.0e-5, 100));
        assertFraction(1, 7, new BigFraction((double) 1 / (double) 7, 1.0e-5, 100));
        assertFraction(2, 7, new BigFraction((double) 2 / (double) 7, 1.0e-5, 100));
        assertFraction(3, 7, new BigFraction((double) 3 / (double) 7, 1.0e-5, 100));
        assertFraction(4, 7, new BigFraction((double) 4 / (double) 7, 1.0e-5, 100));
        assertFraction(5, 7, new BigFraction((double) 5 / (double) 7, 1.0e-5, 100));
        assertFraction(6, 7, new BigFraction((double) 6 / (double) 7, 1.0e-5, 100));
        assertFraction(1, 8, new BigFraction((double) 1 / (double) 8, 1.0e-5, 100));
        assertFraction(3, 8, new BigFraction((double) 3 / (double) 8, 1.0e-5, 100));
        assertFraction(5, 8, new BigFraction((double) 5 / (double) 8, 1.0e-5, 100));
        assertFraction(7, 8, new BigFraction((double) 7 / (double) 8, 1.0e-5, 100));
        assertFraction(1, 9, new BigFraction((double) 1 / (double) 9, 1.0e-5, 100));
        assertFraction(2, 9, new BigFraction((double) 2 / (double) 9, 1.0e-5, 100));
        assertFraction(4, 9, new BigFraction((double) 4 / (double) 9, 1.0e-5, 100));
        assertFraction(5, 9, new BigFraction((double) 5 / (double) 9, 1.0e-5, 100));
        assertFraction(7, 9, new BigFraction((double) 7 / (double) 9, 1.0e-5, 100));
        assertFraction(8, 9, new BigFraction((double) 8 / (double) 9, 1.0e-5, 100));
        assertFraction(1, 10, new BigFraction((double) 1 / (double) 10, 1.0e-5, 100));
        assertFraction(3, 10, new BigFraction((double) 3 / (double) 10, 1.0e-5, 100));
        assertFraction(7, 10, new BigFraction((double) 7 / (double) 10, 1.0e-5, 100));
        assertFraction(9, 10, new BigFraction((double) 9 / (double) 10, 1.0e-5, 100));
        assertFraction(1, 11, new BigFraction((double) 1 / (double) 11, 1.0e-5, 100));
        assertFraction(2, 11, new BigFraction((double) 2 / (double) 11, 1.0e-5, 100));
        assertFraction(3, 11, new BigFraction((double) 3 / (double) 11, 1.0e-5, 100));
        assertFraction(4, 11, new BigFraction((double) 4 / (double) 11, 1.0e-5, 100));
        assertFraction(5, 11, new BigFraction((double) 5 / (double) 11, 1.0e-5, 100));
        assertFraction(6, 11, new BigFraction((double) 6 / (double) 11, 1.0e-5, 100));
        assertFraction(7, 11, new BigFraction((double) 7 / (double) 11, 1.0e-5, 100));
        assertFraction(8, 11, new BigFraction((double) 8 / (double) 11, 1.0e-5, 100));
        assertFraction(9, 11, new BigFraction((double) 9 / (double) 11, 1.0e-5, 100));
        assertFraction(10, 11, new BigFraction((double) 10 / (double) 11, 1.0e-5, 100));
    }

    // MATH-181
    public void testDigitLimitConstructor() throws ConvergenceException {
        assertFraction(2, 5, new BigFraction(0.4, 9));
        assertFraction(2, 5, new BigFraction(0.4, 99));
        assertFraction(2, 5, new BigFraction(0.4, 999));

        assertFraction(3, 5, new BigFraction(0.6152, 9));
        assertFraction(8, 13, new BigFraction(0.6152, 99));
        assertFraction(510, 829, new BigFraction(0.6152, 999));
        assertFraction(769, 1250, new BigFraction(0.6152, 9999));
    }

    public void testEpsilonLimitConstructor() throws ConvergenceException {
        assertFraction(2, 5, new BigFraction(0.4, 1.0e-5, 100));

        assertFraction(3, 5, new BigFraction(0.6152, 0.02, 100));
        assertFraction(8, 13, new BigFraction(0.6152, 1.0e-3, 100));
        assertFraction(251, 408, new BigFraction(0.6152, 1.0e-4, 100));
        assertFraction(251, 408, new BigFraction(0.6152, 1.0e-5, 100));
        assertFraction(510, 829, new BigFraction(0.6152, 1.0e-6, 100));
        assertFraction(769, 1250, new BigFraction(0.6152, 1.0e-7, 100));
    }

    public void testCompareTo() {
        BigFraction first = new BigFraction(1, 2);
        BigFraction second = new BigFraction(1, 3);
        BigFraction third = new BigFraction(1, 2);

        assertEquals(0, first.compareTo(first));
        assertEquals(0, first.compareTo(third));
        assertEquals(1, first.compareTo(second));
        assertEquals(-1, second.compareTo(first));

        // these two values are different approximations of PI
        // the first  one is approximately PI - 3.07e-18
        // the second one is approximately PI + 1.936e-17
        BigFraction pi1 = new BigFraction(1068966896, 340262731);
        BigFraction pi2 = new BigFraction( 411557987, 131002976);
        assertEquals(-1, pi1.compareTo(pi2));
        assertEquals( 1, pi2.compareTo(pi1));
        assertEquals(0.0, pi1.doubleValue() - pi2.doubleValue(), 1.0e-20);

    }

    public void testDoubleValue() {
        BigFraction first = new BigFraction(1, 2);
        BigFraction second = new BigFraction(1, 3);

        assertEquals(0.5, first.doubleValue(), 0.0);
        assertEquals(1.0 / 3.0, second.doubleValue(), 0.0);
    }

    public void testFloatValue() {
        BigFraction first = new BigFraction(1, 2);
        BigFraction second = new BigFraction(1, 3);

        assertEquals(0.5f, first.floatValue(), 0.0f);
        assertEquals((float) (1.0 / 3.0), second.floatValue(), 0.0f);
    }

    public void testIntValue() {
        BigFraction first = new BigFraction(1, 2);
        BigFraction second = new BigFraction(3, 2);

        assertEquals(0, first.intValue());
        assertEquals(1, second.intValue());
    }

    public void testLongValue() {
        BigFraction first = new BigFraction(1, 2);
        BigFraction second = new BigFraction(3, 2);

        assertEquals(0L, first.longValue());
        assertEquals(1L, second.longValue());
    }

    public void testConstructorDouble() {
        assertFraction(1, 2, new BigFraction(0.5));
        assertFraction(6004799503160661l, 18014398509481984l, new BigFraction(1.0 / 3.0));
        assertFraction(6124895493223875l, 36028797018963968l, new BigFraction(17.0 / 100.0));
        assertFraction(1784551352345559l, 562949953421312l, new BigFraction(317.0 / 100.0));
        assertFraction(-1, 2, new BigFraction(-0.5));
        assertFraction(-6004799503160661l, 18014398509481984l, new BigFraction(-1.0 / 3.0));
        assertFraction(-6124895493223875l, 36028797018963968l, new BigFraction(17.0 / -100.0));
        assertFraction(-1784551352345559l, 562949953421312l, new BigFraction(-317.0 / 100.0));
        for (double v : new double[] { Double.NaN, Double.NEGATIVE_INFINITY, Double.POSITIVE_INFINITY}) {
            try {
                new BigFraction(v);
                fail("expected exception");
            } catch (IllegalArgumentException iae) {
                // expected
            }
        }
        assertEquals(1l, new BigFraction(Double.MAX_VALUE).getDenominatorAsLong());
        assertEquals(1l, new BigFraction(Double.longBitsToDouble(0x0010000000000000L)).getNumeratorAsLong());
        assertEquals(1l, new BigFraction(Double.MIN_VALUE).getNumeratorAsLong());
    }

    public void testAbs() {
        BigFraction a = new BigFraction(10, 21);
        BigFraction b = new BigFraction(-10, 21);
        BigFraction c = new BigFraction(10, -21);

        assertFraction(10, 21, a.abs());
        assertFraction(10, 21, b.abs());
        assertFraction(10, 21, c.abs());
    }

    public void testReciprocal() {
        BigFraction f = null;

        f = new BigFraction(50, 75);
        f = f.reciprocal();
        assertEquals(3, f.getNumeratorAsInt());
        assertEquals(2, f.getDenominatorAsInt());

        f = new BigFraction(4, 3);
        f = f.reciprocal();
        assertEquals(3, f.getNumeratorAsInt());
        assertEquals(4, f.getDenominatorAsInt());

        f = new BigFraction(-15, 47);
        f = f.reciprocal();
        assertEquals(-47, f.getNumeratorAsInt());
        assertEquals(15, f.getDenominatorAsInt());

        f = new BigFraction(0, 3);
        try {
            f = f.reciprocal();
            fail("expecting ArithmeticException");
        } catch (ArithmeticException ex) {
        }

        // large values
        f = new BigFraction(Integer.MAX_VALUE, 1);
        f = f.reciprocal();
        assertEquals(1, f.getNumeratorAsInt());
        assertEquals(Integer.MAX_VALUE, f.getDenominatorAsInt());
    }

    public void testNegate() {
        BigFraction f = null;

        f = new BigFraction(50, 75);
        f = f.negate();
        assertEquals(-2, f.getNumeratorAsInt());
        assertEquals(3, f.getDenominatorAsInt());

        f = new BigFraction(-50, 75);
        f = f.negate();
        assertEquals(2, f.getNumeratorAsInt());
        assertEquals(3, f.getDenominatorAsInt());

        // large values
        f = new BigFraction(Integer.MAX_VALUE - 1, Integer.MAX_VALUE);
        f = f.negate();
        assertEquals(Integer.MIN_VALUE + 2, f.getNumeratorAsInt());
        assertEquals(Integer.MAX_VALUE, f.getDenominatorAsInt());

    }

    public void testAdd() {
        BigFraction a = new BigFraction(1, 2);
        BigFraction b = new BigFraction(2, 3);

        assertFraction(1, 1, a.add(a));
        assertFraction(7, 6, a.add(b));
        assertFraction(7, 6, b.add(a));
        assertFraction(4, 3, b.add(b));

        BigFraction f1 = new BigFraction(Integer.MAX_VALUE - 1, 1);
        BigFraction f2 = BigFraction.ONE;
        BigFraction f = f1.add(f2);
        assertEquals(Integer.MAX_VALUE, f.getNumeratorAsInt());
        assertEquals(1, f.getDenominatorAsInt());

        f1 = new BigFraction(-1, 13 * 13 * 2 * 2);
        f2 = new BigFraction(-2, 13 * 17 * 2);
        f = f1.add(f2);
        assertEquals(13 * 13 * 17 * 2 * 2, f.getDenominatorAsInt());
        assertEquals(-17 - 2 * 13 * 2, f.getNumeratorAsInt());

        try {
            f.add((BigFraction) null);
            fail("expecting NullPointerException");
        } catch (NullPointerException ex) {
        }

        // if this fraction is added naively, it will overflow.
        // check that it doesn't.
        f1 = new BigFraction(1, 32768 * 3);
        f2 = new BigFraction(1, 59049);
        f = f1.add(f2);
        assertEquals(52451, f.getNumeratorAsInt());
        assertEquals(1934917632, f.getDenominatorAsInt());

        f1 = new BigFraction(Integer.MIN_VALUE, 3);
        f2 = new BigFraction(1, 3);
        f = f1.add(f2);
        assertEquals(Integer.MIN_VALUE + 1, f.getNumeratorAsInt());
        assertEquals(3, f.getDenominatorAsInt());

        f1 = new BigFraction(Integer.MAX_VALUE - 1, 1);
        f = f1.add(BigInteger.ONE);
        assertEquals(Integer.MAX_VALUE, f.getNumeratorAsInt());
        assertEquals(1, f.getDenominatorAsInt());

        f = f.add(BigInteger.ZERO);
        assertEquals(Integer.MAX_VALUE, f.getNumeratorAsInt());
        assertEquals(1, f.getDenominatorAsInt());

        f1 = new BigFraction(Integer.MAX_VALUE - 1, 1);
        f = f1.add(1);
        assertEquals(Integer.MAX_VALUE, f.getNumeratorAsInt());
        assertEquals(1, f.getDenominatorAsInt());

        f = f.add(0);
        assertEquals(Integer.MAX_VALUE, f.getNumeratorAsInt());
        assertEquals(1, f.getDenominatorAsInt());

        f1 = new BigFraction(Integer.MAX_VALUE - 1, 1);
        f = f1.add(1l);
        assertEquals(Integer.MAX_VALUE, f.getNumeratorAsInt());
        assertEquals(1, f.getDenominatorAsInt());

        f = f.add(0l);
        assertEquals(Integer.MAX_VALUE, f.getNumeratorAsInt());
        assertEquals(1, f.getDenominatorAsInt());

    }

    public void testDivide() {
        BigFraction a = new BigFraction(1, 2);
        BigFraction b = new BigFraction(2, 3);

        assertFraction(1, 1, a.divide(a));
        assertFraction(3, 4, a.divide(b));
        assertFraction(4, 3, b.divide(a));
        assertFraction(1, 1, b.divide(b));

        BigFraction f1 = new BigFraction(3, 5);
        BigFraction f2 = BigFraction.ZERO;
        try {
            f1.divide(f2);
            fail("expecting ArithmeticException");
        } catch (ArithmeticException ex) {
        }

        f1 = new BigFraction(0, 5);
        f2 = new BigFraction(2, 7);
        BigFraction f = f1.divide(f2);
        assertSame(BigFraction.ZERO, f);

        f1 = new BigFraction(2, 7);
        f2 = BigFraction.ONE;
        f = f1.divide(f2);
        assertEquals(2, f.getNumeratorAsInt());
        assertEquals(7, f.getDenominatorAsInt());

        f1 = new BigFraction(1, Integer.MAX_VALUE);
        f = f1.divide(f1);
        assertEquals(1, f.getNumeratorAsInt());
        assertEquals(1, f.getDenominatorAsInt());

        f1 = new BigFraction(Integer.MIN_VALUE, Integer.MAX_VALUE);
        f2 = new BigFraction(1, Integer.MAX_VALUE);
        f = f1.divide(f2);
        assertEquals(Integer.MIN_VALUE, f.getNumeratorAsInt());
        assertEquals(1, f.getDenominatorAsInt());

        try {
            f.divide((BigFraction) null);
            fail("expecting NullPointerException");
        } catch (NullPointerException ex) {
        }

        f1 = new BigFraction(Integer.MIN_VALUE, Integer.MAX_VALUE);
        f = f1.divide(BigInteger.valueOf(Integer.MIN_VALUE));
        assertEquals(Integer.MAX_VALUE, f.getDenominatorAsInt());
        assertEquals(1, f.getNumeratorAsInt());

        f1 = new BigFraction(Integer.MIN_VALUE, Integer.MAX_VALUE);
        f = f1.divide(Integer.MIN_VALUE);
        assertEquals(Integer.MAX_VALUE, f.getDenominatorAsInt());
        assertEquals(1, f.getNumeratorAsInt());

        f1 = new BigFraction(Integer.MIN_VALUE, Integer.MAX_VALUE);
        f = f1.divide((long) Integer.MIN_VALUE);
        assertEquals(Integer.MAX_VALUE, f.getDenominatorAsInt());
        assertEquals(1, f.getNumeratorAsInt());

    }

    public void testMultiply() {
        BigFraction a = new BigFraction(1, 2);
        BigFraction b = new BigFraction(2, 3);

        assertFraction(1, 4, a.multiply(a));
        assertFraction(1, 3, a.multiply(b));
        assertFraction(1, 3, b.multiply(a));
        assertFraction(4, 9, b.multiply(b));

        BigFraction f1 = new BigFraction(Integer.MAX_VALUE, 1);
        BigFraction f2 = new BigFraction(Integer.MIN_VALUE, Integer.MAX_VALUE);
        BigFraction f = f1.multiply(f2);
        assertEquals(Integer.MIN_VALUE, f.getNumeratorAsInt());
        assertEquals(1, f.getDenominatorAsInt());

        f = f2.multiply(Integer.MAX_VALUE);
        assertEquals(Integer.MIN_VALUE, f.getNumeratorAsInt());
        assertEquals(1, f.getDenominatorAsInt());

        f = f2.multiply((long) Integer.MAX_VALUE);
        assertEquals(Integer.MIN_VALUE, f.getNumeratorAsInt());
        assertEquals(1, f.getDenominatorAsInt());

        try {
            f.multiply((BigFraction) null);
            fail("expecting NullPointerException");
        } catch (NullPointerException ex) {
        }

    }

    public void testSubtract() {
        BigFraction a = new BigFraction(1, 2);
        BigFraction b = new BigFraction(2, 3);

        assertFraction(0, 1, a.subtract(a));
        assertFraction(-1, 6, a.subtract(b));
        assertFraction(1, 6, b.subtract(a));
        assertFraction(0, 1, b.subtract(b));

        BigFraction f = new BigFraction(1, 1);
        try {
            f.subtract((BigFraction) null);
            fail("expecting NullPointerException");
        } catch (NullPointerException ex) {
        }

        // if this fraction is subtracted naively, it will overflow.
        // check that it doesn't.
        BigFraction f1 = new BigFraction(1, 32768 * 3);
        BigFraction f2 = new BigFraction(1, 59049);
        f = f1.subtract(f2);
        assertEquals(-13085, f.getNumeratorAsInt());
        assertEquals(1934917632, f.getDenominatorAsInt());

        f1 = new BigFraction(Integer.MIN_VALUE, 3);
        f2 = new BigFraction(1, 3).negate();
        f = f1.subtract(f2);
        assertEquals(Integer.MIN_VALUE + 1, f.getNumeratorAsInt());
        assertEquals(3, f.getDenominatorAsInt());

        f1 = new BigFraction(Integer.MAX_VALUE, 1);
        f2 = BigFraction.ONE;
        f = f1.subtract(f2);
        assertEquals(Integer.MAX_VALUE - 1, f.getNumeratorAsInt());
        assertEquals(1, f.getDenominatorAsInt());

    }

    public void testBigDecimalValue() {
        assertEquals(new BigDecimal(0.5), new BigFraction(1, 2).bigDecimalValue());
        assertEquals(new BigDecimal("0.0003"), new BigFraction(3, 10000).bigDecimalValue());
        assertEquals(new BigDecimal("0"), new BigFraction(1, 3).bigDecimalValue(BigDecimal.ROUND_DOWN));
        assertEquals(new BigDecimal("0.333"), new BigFraction(1, 3).bigDecimalValue(3, BigDecimal.ROUND_DOWN));
    }

    public void testEqualsAndHashCode() {
        BigFraction zero = new BigFraction(0, 1);
        BigFraction nullFraction = null;
        assertTrue(zero.equals(zero));
        assertFalse(zero.equals(nullFraction));
        assertFalse(zero.equals(Double.valueOf(0)));
        BigFraction zero2 = new BigFraction(0, 2);
        assertTrue(zero.equals(zero2));
        assertEquals(zero.hashCode(), zero2.hashCode());
        BigFraction one = new BigFraction(1, 1);
        assertFalse((one.equals(zero) || zero.equals(one)));
        assertTrue(one.equals(BigFraction.ONE));
    }

    public void testGetReducedFraction() {
        BigFraction threeFourths = new BigFraction(3, 4);
        assertTrue(threeFourths.equals(BigFraction.getReducedFraction(6, 8)));
        assertTrue(BigFraction.ZERO.equals(BigFraction.getReducedFraction(0, -1)));
        try {
            BigFraction.getReducedFraction(1, 0);
            fail("expecting ArithmeticException");
        } catch (ArithmeticException ex) {
            // expected
        }
        assertEquals(BigFraction.getReducedFraction(2, Integer.MIN_VALUE).getNumeratorAsInt(), -1);
        assertEquals(BigFraction.getReducedFraction(1, -1).getNumeratorAsInt(), -1);
    }

    public void testPow() {
        assertEquals(new BigFraction(8192, 1594323), new BigFraction(2, 3).pow(13));
        assertEquals(new BigFraction(8192, 1594323), new BigFraction(2, 3).pow(13l));
        assertEquals(new BigFraction(8192, 1594323), new BigFraction(2, 3).pow(BigInteger.valueOf(13l)));
        assertEquals(BigFraction.ONE, new BigFraction(2, 3).pow(0));
        assertEquals(BigFraction.ONE, new BigFraction(2, 3).pow(0l));
        assertEquals(BigFraction.ONE, new BigFraction(2, 3).pow(BigInteger.valueOf(0l)));
        assertEquals(new BigFraction(1594323, 8192), new BigFraction(2, 3).pow(-13));
        assertEquals(new BigFraction(1594323, 8192), new BigFraction(2, 3).pow(-13l));
        assertEquals(new BigFraction(1594323, 8192), new BigFraction(2, 3).pow(BigInteger.valueOf(-13l)));
    }

    public void testMath340() {
        BigFraction fractionA = new BigFraction(0.00131);
        BigFraction fractionB = new BigFraction(.37).reciprocal();
        BigFraction errorResult = fractionA.multiply(fractionB);
        BigFraction correctResult = new BigFraction(fractionA.getNumerator().multiply(fractionB.getNumerator()),
                                                    fractionA.getDenominator().multiply(fractionB.getDenominator()));
        assertEquals(correctResult, errorResult);
    }

    public void testSerial() throws FractionConversionException {
        BigFraction[] fractions = {
            new BigFraction(3, 4), BigFraction.ONE, BigFraction.ZERO,
            new BigFraction(17), new BigFraction(Math.PI, 1000),
            new BigFraction(-5, 2)
        };
        for (BigFraction fraction : fractions) {
            assertEquals(fraction, TestUtils.serializeAndRecover(fraction));
        }
    }

}

Other Commons Math examples (source code examples)

Here is a short list of links related to this Commons Math BigFractionTest.java source code file:

... this post is sponsored by my books ...

#1 New Release!

FP Best Seller

 

new blog posts

 

Copyright 1998-2021 Alvin Alexander, alvinalexander.com
All Rights Reserved.

A percentage of advertising revenue from
pages under the /java/jwarehouse URI on this website is
paid back to open source projects.