DDIOTest.java
/*
* Copyright (c) 2016 Martin Davis.
*
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License 2.0
* and Eclipse Distribution License v. 1.0 which accompanies this distribution.
* The Eclipse Public License is available at http://www.eclipse.org/legal/epl-v20.html
* and the Eclipse Distribution License is available at
*
* http://www.eclipse.org/org/documents/edl-v10.php.
*/
package org.locationtech.jts.math;
import junit.framework.TestCase;
import junit.textui.TestRunner;
/**
* Tests I/O for {@link DD}s.
*
* @author mbdavis
*
*/
public class DDIOTest extends TestCase {
public static void main(String args[]) {
TestRunner.run(DDIOTest.class);
}
public DDIOTest(String name) {
super(name);
}
public void testWriteStandardNotation()
{
// standard cases
checkStandardNotation(1.0, "1.0");
checkStandardNotation(0.0, "0.0");
// cases where hi is a power of 10 and lo is negative
checkStandardNotation(DD.valueOf(1e12).subtract(DD.valueOf(1)), "999999999999.0");
checkStandardNotation(DD.valueOf(1e14).subtract(DD.valueOf(1)), "99999999999999.0");
checkStandardNotation(DD.valueOf(1e16).subtract(DD.valueOf(1)), "9999999999999999.0");
DD num8Dec = DD.valueOf(-379363639).divide(
DD.valueOf(100000000));
checkStandardNotation(num8Dec, "-3.79363639");
checkStandardNotation(new DD(-3.79363639, 8.039137357367426E-17),
"-3.7936363900000000000000000");
checkStandardNotation(DD.valueOf(34).divide(
DD.valueOf(1000)), "0.034");
checkStandardNotation(1.05e3, "1050.0");
checkStandardNotation(0.34, "0.34000000000000002442490654175344");
checkStandardNotation(DD.valueOf(34).divide(
DD.valueOf(100)), "0.34");
checkStandardNotation(14, "14.0");
}
private void checkStandardNotation(double x, String expectedStr) {
checkStandardNotation(DD.valueOf(x), expectedStr);
}
private void checkStandardNotation(DD x, String expectedStr) {
String xStr = x.toStandardNotation();
//System.out.println("Standard Notation: " + xStr);
assertEquals(expectedStr, xStr);
}
public void testWriteSciNotation() {
checkSciNotation(0.0, "0.0E0");
checkSciNotation(1.05e10, "1.05E10");
checkSciNotation(0.34, "3.4000000000000002442490654175344E-1");
checkSciNotation(
DD.valueOf(34).divide(DD.valueOf(100)), "3.4E-1");
checkSciNotation(14, "1.4E1");
}
private void checkSciNotation(double x, String expectedStr) {
checkSciNotation(DD.valueOf(x), expectedStr);
}
private void checkSciNotation(DD x, String expectedStr) {
String xStr = x.toSciNotation();
//System.out.println("Sci Notation: " + xStr);
assertEquals(xStr, expectedStr);
}
public void testParseInt() {
checkParse("0", 0, 1e-32);
checkParse("00", 0, 1e-32);
checkParse("000", 0, 1e-32);
checkParse("1", 1, 1e-32);
checkParse("100", 100, 1e-32);
checkParse("00100", 100, 1e-32);
checkParse("-1", -1, 1e-32);
checkParse("-01", -1, 1e-32);
checkParse("-123", -123, 1e-32);
checkParse("-00123", -123, 1e-32);
}
public void testParseStandardNotation() {
checkParse("1.0000000", 1, 1e-32);
checkParse("1.0", 1, 1e-32);
checkParse("1.", 1, 1e-32);
checkParse("01.", 1, 1e-32);
checkParse("-1.0", -1, 1e-32);
checkParse("-1.", -1, 1e-32);
checkParse("-01.0", -1, 1e-32);
checkParse("-123.0", -123, 1e-32);
/*
* The Java double-precision constant 1.4 gives rise to a value which
* differs from the exact binary representation down around the 17th decimal
* place. Thus it will not compare exactly to the DoubleDouble
* representation of the same number. To avoid this, compute the expected
* value using full DD precision.
*/
checkParse("1.4",
DD.valueOf(14).divide(DD.valueOf(10)), 1e-30);
// 39.5D can be converted to an exact FP representation
checkParse("39.5", 39.5, 1e-30);
checkParse("-39.5", -39.5, 1e-30);
}
public void testParseSciNotation() {
checkParse("1.05e10", 1.05E10, 1e-32);
checkParse("01.05e10", 1.05E10, 1e-32);
checkParse("12.05e10", 1.205E11, 1e-32);
checkParse("-1.05e10", -1.05E10, 1e-32);
checkParse("1.05e-10", DD.valueOf(105.).divide(
DD.valueOf(100.)).divide(DD.valueOf(1.0E10)), 1e-32);
checkParse("-1.05e-10", DD.valueOf(105.).divide(
DD.valueOf(100.)).divide(DD.valueOf(1.0E10))
.negate(), 1e-32);
}
private void checkParse(String str, double expectedVal, double errBound) {
checkParse(str, new DD(expectedVal), errBound);
}
private void checkParse(String str, DD expectedVal,
double relErrBound) {
DD xdd = DD.parse(str);
double err = xdd.subtract(expectedVal).doubleValue();
double xddd = xdd.doubleValue();
double relErr = xddd == 0d ? err : Math.abs(err / xddd);
//System.out.println("Parsed= " + xdd + " rel err= " + relErr);
assertTrue("parsing '" + str + "' results in " + xdd.toString() + " ( "
+ xdd.dump() + ") != " + expectedVal + "\n err =" + err + ", relerr =" + relErr, relErr <= relErrBound);
}
public void testParseError() {
checkParseError("-1.05E2w");
checkParseError("%-1.05E2w");
checkParseError("-1.0512345678t");
}
private void checkParseError(String str) {
boolean foundParseError = false;
try {
DD.parse(str);
} catch (NumberFormatException ex) {
foundParseError = true;
}
assertTrue(foundParseError);
}
public void testWriteRepeatedSqrt()
{
writeRepeatedSqrt(DD.valueOf(1.0));
writeRepeatedSqrt(DD.valueOf(.999999999999));
writeRepeatedSqrt(DD.PI.divide(DD.valueOf(10)));
}
/**
* This routine simply tests for robustness of the toString function.
*
* @param xdd the value to test (write and parse)
*/
private void writeRepeatedSqrt(DD xdd)
{
int count = 0;
while (xdd.doubleValue() > 1e-300) {
count++;
double x = xdd.doubleValue();
DD xSqrt = xdd.sqrt();
String s = xSqrt.toString();
// System.out.println(count + ": " + s);
DD xSqrt2 = DD.parse(s);
DD xx = xSqrt2.multiply(xSqrt2);
double err = Math.abs(xx.doubleValue() - x);
//assertTrue(err < 1e-10);
xdd = xSqrt;
// square roots converge on 1 - stop when very close
DD distFrom1DD = xSqrt.subtract(DD.valueOf(1.0));
double distFrom1 = distFrom1DD.doubleValue();
if (Math.abs(distFrom1) < 1.0e-40)
break;
}
}
public void testWriteRepeatedSqr()
{
writeRepeatedSqr(DD.valueOf(.9));
writeRepeatedSqr(DD.PI.divide(DD.valueOf(10)));
}
/**
* This routine simply tests for robustness of the toString function.
*
* @param xdd the value to test (write and parse)
*/
private void writeRepeatedSqr(DD xdd)
{
if (xdd.ge(DD.valueOf(1)))
throw new IllegalArgumentException("Argument must be < 1");
int count = 0;
while (xdd.doubleValue() > 1e-300) {
count++;
if (count == 100)
count = count;
double x = xdd.doubleValue();
DD xSqr = xdd.sqr();
String s = xSqr.toString();
//System.out.println(count + ": " + s);
DD xSqr2 = DD.parse(s);
xdd = xSqr;
}
}
public void testWriteSquaresStress() {
for (int i = 1; i < 10000; i++) {
writeAndReadSqrt(i);
}
}
/**
* Tests that printing values with many decimal places works.
* This tests the correctness and robustness of both output and input.
*
* @param x the value to test
*/
private void writeAndReadSqrt(double x) {
DD xdd = DD.valueOf(x);
DD xSqrt = xdd.sqrt();
String s = xSqrt.toString();
// System.out.println(s);
DD xSqrt2 = DD.parse(s);
DD xx = xSqrt2.multiply(xSqrt2);
String xxStr = xx.toString();
// System.out.println("==> " + xxStr);
DD xx2 = DD.parse(xxStr);
double err = Math.abs(xx2.doubleValue() - x);
assertTrue(err < 1e-10);
}
}