Multimodule project setup.

Created "core", "complex" and "quaternion" modules.


Project: http://git-wip-us.apache.org/repos/asf/commons-numbers/repo
Commit: http://git-wip-us.apache.org/repos/asf/commons-numbers/commit/c4541327
Tree: http://git-wip-us.apache.org/repos/asf/commons-numbers/tree/c4541327
Diff: http://git-wip-us.apache.org/repos/asf/commons-numbers/diff/c4541327

Branch: refs/heads/multimodule
Commit: c45413279a7e1eec230516ec1f8efd5456c6215e
Parents: a752ab8
Author: Gilles Sadowski <[email protected]>
Authored: Wed Jan 18 14:22:45 2017 +0100
Committer: Gilles Sadowski <[email protected]>
Committed: Wed Jan 18 14:22:45 2017 +0100

----------------------------------------------------------------------
 NOTICE.txt                                      |    2 +-
 README.md                                       |   23 +-
 commons-numbers-complex/LICENSE.txt             |  201 +++
 commons-numbers-complex/NOTICE.txt              |    6 +
 commons-numbers-complex/README.md               |   98 ++
 commons-numbers-complex/pom.xml                 |   61 +
 .../apache/commons/numbers/complex/Complex.java | 1369 ++++++++++++++++
 .../commons/numbers/complex/ComplexUtils.java   | 1430 +++++++++++++++++
 .../commons/numbers/complex/Precision.java      |  128 ++
 .../commons/numbers/complex/RootsOfUnity.java   |  116 ++
 .../commons/numbers/complex/package-info.java   |   20 +
 .../commons/numbers/complex/ComplexTest.java    | 1477 ++++++++++++++++++
 .../numbers/complex/ComplexUtilsTest.java       |  475 ++++++
 .../numbers/complex/RootsOfUnityTest.java       |   84 +
 .../commons/numbers/complex/TestUtils.java      |  409 +++++
 commons-numbers-core/LICENSE.txt                |  201 +++
 commons-numbers-core/NOTICE.txt                 |    6 +
 commons-numbers-core/README.md                  |   98 ++
 commons-numbers-core/pom.xml                    |   46 +
 .../apache/commons/numbers/core/Precision.java  |  598 +++++++
 .../commons/numbers/core/PrecisionTest.java     |  547 +++++++
 .../apache/commons/numbers/core/TestUtils.java  |  320 ++++
 commons-numbers-quaternion/LICENSE.txt          |  201 +++
 commons-numbers-quaternion/NOTICE.txt           |    6 +
 commons-numbers-quaternion/README.md            |   98 ++
 commons-numbers-quaternion/pom.xml              |   53 +
 .../commons/numbers/quaternion/Quaternion.java  |  455 ++++++
 .../numbers/quaternion/package-info.java        |   20 +
 .../numbers/quaternion/QuaternionTest.java      |  456 ++++++
 pom.xml                                         |  408 ++---
 src/main/resources/checkstyle/checkstyle.xml    |  202 +++
 .../resources/checkstyle/license-header.txt     |   16 +
 src/main/resources/clirr/clirr-ignored.xml      |   21 +
 .../findbugs/findbugs-exclude-filter.xml        |   28 +
 src/main/resources/pmd/pmd-ruleset.xml          |   57 +
 35 files changed, 9530 insertions(+), 206 deletions(-)
----------------------------------------------------------------------


http://git-wip-us.apache.org/repos/asf/commons-numbers/blob/c4541327/NOTICE.txt
----------------------------------------------------------------------
diff --git a/NOTICE.txt b/NOTICE.txt
index d22df2a..ea6ae07 100644
--- a/NOTICE.txt
+++ b/NOTICE.txt
@@ -1,4 +1,4 @@
-Apache Commons Math
+Apache Commons Numbers
 Copyright 2001-2016 The Apache Software Foundation
 
 This product includes software developed at

http://git-wip-us.apache.org/repos/asf/commons-numbers/blob/c4541327/README.md
----------------------------------------------------------------------
diff --git a/README.md b/README.md
index 905ee17..e0754e0 100644
--- a/README.md
+++ b/README.md
@@ -40,33 +40,28 @@
  |                                                                      |
  +======================================================================+
 --->
-Apache Commons Complex
-======================
+Apache Commons Numbers
+===================
 
-[![Build 
Status](https://travis-ci.org/apache/commons-complex.svg?branch=master)](https://travis-ci.org/apache/commons-complex)
-[![Coverage 
Status](https://coveralls.io/repos/apache/commons-complex/badge.svg?branch=master&service=github)](https://coveralls.io/github/apache/commons-complex?branch=master)
-[![Maven 
Central](https://maven-badges.herokuapp.com/maven-central/org.apache.commons/commons-complex/badge.svg)](https://maven-badges.herokuapp.com/maven-central/org.apache.commons/commons-complex/)
-[![License](http://img.shields.io/:license-apache-blue.svg)](http://www.apache.org/licenses/LICENSE-2.0.html)
-
-The Apache Commons Complex project provides self-contained components 
addressing the most common practical problems involving Java computing with 
complex numbers.
+The Apache Commons Numbers project provides number types and utilities.
 
 Documentation
 -------------
 
-More information can be found on the 
[homepage](https://commons.apache.org/proper/commons-complex).
-The [JavaDoc](https://commons.apache.org/proper/commons-complex/apidocs) can 
be browsed.
-Questions related to the usage of Apache Commons Math should be posted to the 
[user mailing list][ml].
+More information can be found on the 
[homepage](https://commons.apache.org/proper/commons-numbers).
+The 
[JavaDoc](https://commons.apache.org/proper/commons-numbers/javadocs/api-release)
 can be browsed.
+Questions related to the usage of Apache Commons Numbers should be posted to 
the [user mailing list][ml].
 
 Where can I get the latest release?
 -----------------------------------
-You can download source and binaries from our [download 
page](https://commons.apache.org/proper/commons-complex/download_complex.cgi).
+You can download source and binaries from our [download 
page](https://commons.apache.org/proper/commons-numbers/download_numbers.cgi).
 
 Alternatively you can pull it from the central Maven repositories:
 
 ```xml
 <dependency>
   <groupId>org.apache.commons</groupId>
-  <artifactId>commons-complex</artifactId>
+  <artifactId>commons-numbers-parent</artifactId>
   <version>1.0</version>
 </dependency>
 ```
@@ -90,7 +85,7 @@ Code is under the [Apache Licence 
v2](https://www.apache.org/licenses/LICENSE-2.
 
 Donations
 ---------
-You like Apache Commons Math? Then [donate back to the 
ASF](https://www.apache.org/foundation/contributing.html) to support the 
development.
+You like Apache Commons Numbers? Then [donate back to the 
ASF](https://www.apache.org/foundation/contributing.html) to support the 
development.
 
 Additional Resources
 --------------------

http://git-wip-us.apache.org/repos/asf/commons-numbers/blob/c4541327/commons-numbers-complex/LICENSE.txt
----------------------------------------------------------------------
diff --git a/commons-numbers-complex/LICENSE.txt 
b/commons-numbers-complex/LICENSE.txt
new file mode 100644
index 0000000..261eeb9
--- /dev/null
+++ b/commons-numbers-complex/LICENSE.txt
@@ -0,0 +1,201 @@
+                                 Apache License
+                           Version 2.0, January 2004
+                        http://www.apache.org/licenses/
+
+   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+   1. Definitions.
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+      "License" shall mean the terms and conditions for use, reproduction,
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+      of this License, Derivative Works shall not include works that remain
+      separable from, or merely link (or bind by name) to the interfaces of,
+      the Work and Derivative Works thereof.
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+      "Contribution" shall mean any work of authorship, including
+      the original version of the Work and any modifications or additions
+      to that Work or Derivative Works thereof, that is intentionally
+      submitted to Licensor for inclusion in the Work by the copyright owner
+      or by an individual or Legal Entity authorized to submit on behalf of
+      the copyright owner. For the purposes of this definition, "submitted"
+      means any form of electronic, verbal, or written communication sent
+      to the Licensor or its representatives, including but not limited to
+      communication on electronic mailing lists, source code control systems,
+      and issue tracking systems that are managed by, or on behalf of, the
+      Licensor for the purpose of discussing and improving the Work, but
+      excluding communication that is conspicuously marked or otherwise
+      designated in writing by the copyright owner as "Not a Contribution."
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+      "Contributor" shall mean Licensor and any individual or Legal Entity
+      on behalf of whom a Contribution has been received by Licensor and
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+   2. Grant of Copyright License. Subject to the terms and conditions of
+      this License, each Contributor hereby grants to You a perpetual,
+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
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+   4. Redistribution. You may reproduce and distribute copies of the
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+      meet the following conditions:
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+
+      (b) You must cause any modified files to carry prominent notices
+          stating that You changed the files; and
+
+      (c) You must retain, in the Source form of any Derivative Works
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+      (d) If the Work includes a "NOTICE" text file as part of its
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+          of the NOTICE file are for informational purposes only and
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+          notices within Derivative Works that You distribute, alongside
+          or as an addendum to the NOTICE text from the Work, provided
+          that such additional attribution notices cannot be construed
+          as modifying the License.
+
+      You may add Your own copyright statement to Your modifications and
+      may provide additional or different license terms and conditions
+      for use, reproduction, or distribution of Your modifications, or
+      for any such Derivative Works as a whole, provided Your use,
+      reproduction, and distribution of the Work otherwise complies with
+      the conditions stated in this License.
+
+   5. Submission of Contributions. Unless You explicitly state otherwise,
+      any Contribution intentionally submitted for inclusion in the Work
+      by You to the Licensor shall be under the terms and conditions of
+      this License, without any additional terms or conditions.
+      Notwithstanding the above, nothing herein shall supersede or modify
+      the terms of any separate license agreement you may have executed
+      with Licensor regarding such Contributions.
+
+   6. Trademarks. This License does not grant permission to use the trade
+      names, trademarks, service marks, or product names of the Licensor,
+      except as required for reasonable and customary use in describing the
+      origin of the Work and reproducing the content of the NOTICE file.
+
+   7. Disclaimer of Warranty. Unless required by applicable law or
+      agreed to in writing, Licensor provides the Work (and each
+      Contributor provides its Contributions) on an "AS IS" BASIS,
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+      risks associated with Your exercise of permissions under this License.
+
+   8. Limitation of Liability. In no event and under no legal theory,
+      whether in tort (including negligence), contract, or otherwise,
+      unless required by applicable law (such as deliberate and grossly
+      negligent acts) or agreed to in writing, shall any Contributor be
+      liable to You for damages, including any direct, indirect, special,
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+   9. Accepting Warranty or Additional Liability. While redistributing
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+      on Your own behalf and on Your sole responsibility, not on behalf
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+      defend, and hold each Contributor harmless for any liability
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+   END OF TERMS AND CONDITIONS
+
+   APPENDIX: How to apply the Apache License to your work.
+
+      To apply the Apache License to your work, attach the following
+      boilerplate notice, with the fields enclosed by brackets "[]"
+      replaced with your own identifying information. (Don't include
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+   Copyright [yyyy] [name of copyright owner]
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+   Licensed 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
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+   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.

http://git-wip-us.apache.org/repos/asf/commons-numbers/blob/c4541327/commons-numbers-complex/NOTICE.txt
----------------------------------------------------------------------
diff --git a/commons-numbers-complex/NOTICE.txt 
b/commons-numbers-complex/NOTICE.txt
new file mode 100644
index 0000000..ea6ae07
--- /dev/null
+++ b/commons-numbers-complex/NOTICE.txt
@@ -0,0 +1,6 @@
+Apache Commons Numbers
+Copyright 2001-2016 The Apache Software Foundation
+
+This product includes software developed at
+The Apache Software Foundation (http://www.apache.org/).
+

http://git-wip-us.apache.org/repos/asf/commons-numbers/blob/c4541327/commons-numbers-complex/README.md
----------------------------------------------------------------------
diff --git a/commons-numbers-complex/README.md 
b/commons-numbers-complex/README.md
new file mode 100644
index 0000000..582b7ce
--- /dev/null
+++ b/commons-numbers-complex/README.md
@@ -0,0 +1,98 @@
+<!---
+ 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.
+-->
+<!---
+ +======================================================================+
+ |****                                                              ****|
+ |****      THIS FILE IS GENERATED BY THE COMMONS BUILD PLUGIN      ****|
+ |****                    DO NOT EDIT DIRECTLY                      ****|
+ |****                                                              ****|
+ +======================================================================+
+ | TEMPLATE FILE: readme-md-template.md                                 |
+ | commons-build-plugin/trunk/src/main/resources/commons-xdoc-templates |
+ +======================================================================+
+ |                                                                      |
+ | 1) Re-generate using: mvn commons:readme-md                          |
+ |                                                                      |
+ | 2) Set the following properties in the component's pom:              |
+ |    - commons.componentid (required, alphabetic, lower case)          |
+ |    - commons.release.version (required)                              |
+ |                                                                      |
+ | 3) Example Properties                                                |
+ |                                                                      |
+ |  <properties>                                                        |
+ |    <commons.componentid>math</commons.componentid>                   |
+ |    <commons.release.version>1.2</commons.release.version>            |
+ |  </properties>                                                       |
+ |                                                                      |
+ +======================================================================+
+--->
+Apache Commons Numbers Complex
+===================
+
+Complex numbers.
+
+Documentation
+-------------
+
+More information can be found on the 
[homepage](https://commons.apache.org/proper/commons-numbers).
+The 
[JavaDoc](https://commons.apache.org/proper/commons-numbers/javadocs/api-release)
 can be browsed.
+Questions related to the usage of Apache Commons Numbers Complex should be 
posted to the [user mailing list][ml].
+
+Where can I get the latest release?
+-----------------------------------
+You can download source and binaries from our [download 
page](https://commons.apache.org/proper/commons-numbers/download_numbers.cgi).
+
+Alternatively you can pull it from the central Maven repositories:
+
+```xml
+<dependency>
+  <groupId>org.apache.commons</groupId>
+  <artifactId>commons-numbers-complex</artifactId>
+  <version>1.0</version>
+</dependency>
+```
+
+Contributing
+------------
+
+We accept PRs via github. The [developer mailing list][ml] is the main channel 
of communication for contributors.
+There are some guidelines which will make applying PRs easier for us:
++ No tabs! Please use spaces for indentation.
++ Respect the code style.
++ Create minimal diffs - disable on save actions like reformat source code or 
organize imports. If you feel the source code should be reformatted create a 
separate PR for this change.
++ Provide JUnit tests for your changes and make sure your changes don't break 
any existing tests by running ```mvn clean test```.
+
+If you plan to contribute on a regular basis, please consider filing a 
[contributor license agreement](https://www.apache.org/licenses/#clas).
+You can learn more about contributing via GitHub in our [contribution 
guidelines](CONTRIBUTING.md).
+
+License
+-------
+Code is under the [Apache Licence 
v2](https://www.apache.org/licenses/LICENSE-2.0.txt).
+
+Donations
+---------
+You like Apache Commons Numbers Complex? Then [donate back to the 
ASF](https://www.apache.org/foundation/contributing.html) to support the 
development.
+
+Additional Resources
+--------------------
+
++ [Apache Commons Homepage](https://commons.apache.org/)
++ [Apache Bugtracker (JIRA)](https://issues.apache.org/jira/)
++ [Apache Commons Twitter Account](https://twitter.com/ApacheCommons)
++ #apachecommons IRC channel on freenode.org
+
+[ml]:https://commons.apache.org/mail-lists.html

http://git-wip-us.apache.org/repos/asf/commons-numbers/blob/c4541327/commons-numbers-complex/pom.xml
----------------------------------------------------------------------
diff --git a/commons-numbers-complex/pom.xml b/commons-numbers-complex/pom.xml
new file mode 100644
index 0000000..735348f
--- /dev/null
+++ b/commons-numbers-complex/pom.xml
@@ -0,0 +1,61 @@
+<?xml version="1.0"?>
+<!--
+   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.
+-->
+<project xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 
http://maven.apache.org/xsd/maven-4.0.0.xsd";
+         xmlns="http://maven.apache.org/POM/4.0.0";
+         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance";>
+  <modelVersion>4.0.0</modelVersion>
+
+  <parent>
+    <groupId>org.apache.commons</groupId>
+    <artifactId>commons-numbers-parent</artifactId>
+    <version>1.0-SNAPSHOT</version>
+  </parent>
+
+  <groupId>org.apache.commons</groupId>
+  <artifactId>commons-numbers-complex</artifactId>
+  <version>1.0-SNAPSHOT</version>
+  <name>Apache Commons Numbers Complex</name>
+
+  <description>Complex numbers.</description>
+
+  <properties>
+    <!-- This value must reflect the current name of the base package. -->
+    
<commons.osgi.symbolicName>org.apache.commons.numbers.complex</commons.osgi.symbolicName>
+    <!-- OSGi -->
+    
<commons.osgi.export>org.apache.commons.numbers.complex</commons.osgi.export>
+    <!-- Workaround to avoid duplicating config files. -->
+    <numbers.parent.dir>${basedir}/..</numbers.parent.dir>
+  </properties>
+
+  <dependencies>
+    <dependency>
+      <groupId>org.apache.commons</groupId>
+      <artifactId>commons-numbers-core</artifactId>
+      <version>1.0-SNAPSHOT</version>
+    </dependency>
+
+    <dependency>
+      <groupId>org.apache.commons</groupId>
+      <artifactId>commons-math3</artifactId>
+      <version>3.6.1</version>
+      <scope>test</scope>
+    </dependency>
+
+  </dependencies>
+
+</project>

http://git-wip-us.apache.org/repos/asf/commons-numbers/blob/c4541327/commons-numbers-complex/src/main/java/org/apache/commons/numbers/complex/Complex.java
----------------------------------------------------------------------
diff --git 
a/commons-numbers-complex/src/main/java/org/apache/commons/numbers/complex/Complex.java
 
b/commons-numbers-complex/src/main/java/org/apache/commons/numbers/complex/Complex.java
new file mode 100644
index 0000000..9581f81
--- /dev/null
+++ 
b/commons-numbers-complex/src/main/java/org/apache/commons/numbers/complex/Complex.java
@@ -0,0 +1,1369 @@
+/*
+ * 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.numbers.complex;
+
+import java.io.Serializable;
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * Representation of a Complex number, i.e. a number which has both a
+ * real and imaginary part.
+ * <p>
+ * Implementations of arithmetic operations handle {@code NaN} and
+ * infinite values according to the rules for {@link java.lang.Double}, i.e.
+ * {@link #equals} is an equivalence relation for all instances that have
+ * a {@code NaN} in either real or imaginary part, e.g. the following are
+ * considered equal:
+ * <ul>
+ *  <li>{@code 1 + NaNi}</li>
+ *  <li>{@code NaN + i}</li>
+ *  <li>{@code NaN + NaNi}</li>
+ * </ul><p>
+ * Note that this contradicts the IEEE-754 standard for floating
+ * point numbers (according to which the test {@code x == x} must fail if
+ * {@code x} is {@code NaN}). The method
+ * {@link 
org.apache.commons.numbers.complex.util.Precision#equals(double,double,int)
+ * equals for primitive double} in {@link 
org.apache.commons.numbers.complex.util.Precision}
+ * conforms with IEEE-754 while this class conforms with the standard behavior
+ * for Java object types.</p>
+ *
+ */
+public class Complex implements Serializable  {
+    /** The square root of -1. A number representing "0.0 + 1.0i" */
+    public static final Complex I = new Complex(0.0, 1.0);
+    // CHECKSTYLE: stop ConstantName
+    /** A complex number representing "NaN + NaNi" */
+    public static final Complex NaN = new Complex(Double.NaN, Double.NaN);
+    // CHECKSTYLE: resume ConstantName
+    /** A complex number representing "+INF + INFi" */
+    public static final Complex INF = new Complex(Double.POSITIVE_INFINITY, 
Double.POSITIVE_INFINITY);
+    /** A complex number representing "1.0 + 0.0i" */
+    public static final Complex ONE = new Complex(1.0, 0.0);
+    /** A complex number representing "0.0 + 0.0i" */
+    public static final Complex ZERO = new Complex(0.0, 0.0);
+
+    /** Serializable version identifier */
+    private static final long serialVersionUID = -6195664516687396620L;
+
+    /** The imaginary part. */
+    private final double imaginary;
+    /** The real part. */
+    private final double real;
+    /** Record whether this complex number is equal to NaN. */
+    private final transient boolean isNaN;
+    /** Record whether this complex number is infinite. */
+    private final transient boolean isInfinite;
+
+    /**
+     * Create a complex number given only the real part.
+     *
+     * @param real Real part.
+     */
+    public Complex(double real) {
+        this(real, 0.0);
+    }
+
+    /**
+     * Create a complex number given the real and imaginary parts.
+     *
+     * @param real Real part.
+     * @param imaginary Imaginary part.
+     */
+    public Complex(double real, double imaginary) {
+        this.real = real;
+        this.imaginary = imaginary;
+
+        isNaN = Double.isNaN(real) || Double.isNaN(imaginary);
+        isInfinite = !isNaN &&
+            (Double.isInfinite(real) || Double.isInfinite(imaginary));
+    }
+
+    /**
+     * Return the absolute value of this complex number.
+     * Returns {@code NaN} if either real or imaginary part is {@code NaN}
+     * and {@code Double.POSITIVE_INFINITY} if neither part is {@code NaN},
+     * but at least one part is infinite.
+     *
+     * @return the absolute value.
+     */
+    public double abs() {
+        if (isNaN) {
+            return Double.NaN;
+        }
+        if (isInfinite()) {
+            return Double.POSITIVE_INFINITY;
+        }
+        if (Math.abs(real) < Math.abs(imaginary)) {
+            if (imaginary == 0.0) {
+                return Math.abs(real);
+            }
+            double q = real / imaginary;
+            return Math.abs(imaginary) * Math.sqrt(1 + q * q);
+        } else {
+            if (real == 0.0) {
+                return Math.abs(imaginary);
+            }
+            double q = imaginary / real;
+            return Math.abs(real) * Math.sqrt(1 + q * q);
+        }
+    }
+
+    /**
+     * Returns a {@code Complex} whose value is
+     * {@code (this + addend)}.
+     * Uses the definitional formula
+     * <p>
+     *   {@code (a + bi) + (c + di) = (a+c) + (b+d)i}
+     * </p>
+     * If either {@code this} or {@code addend} has a {@code NaN} value in
+     * either part, {@link #NaN} is returned; otherwise {@code Infinite}
+     * and {@code NaN} values are returned in the parts of the result
+     * according to the rules for {@link java.lang.Double} arithmetic.
+     *
+     * @param  addend Value to be added to this {@code Complex}.
+     * @return {@code this + addend}.
+     */
+    public Complex add(Complex addend) {
+        checkNotNull(addend);
+        if (isNaN || addend.isNaN) {
+            return NaN;
+        }
+
+        return createComplex(real + addend.getReal(),
+                             imaginary + addend.getImaginary());
+    }
+
+    /**
+     * Returns a {@code Complex} whose value is {@code (this + addend)},
+     * with {@code addend} interpreted as a real number.
+     *
+     * @param addend Value to be added to this {@code Complex}.
+     * @return {@code this + addend}.
+     * @see #add(Complex)
+     */
+    public Complex add(double addend) {
+        if (isNaN || Double.isNaN(addend)) {
+            return NaN;
+        }
+
+        return createComplex(real + addend, imaginary);
+    }
+
+     /**
+     * Returns the conjugate of this complex number.
+     * The conjugate of {@code a + bi} is {@code a - bi}.
+     * <p>
+     * {@link #NaN} is returned if either the real or imaginary
+     * part of this Complex number equals {@code Double.NaN}.
+     * </p><p>
+     * If the imaginary part is infinite, and the real part is not
+     * {@code NaN}, the returned value has infinite imaginary part
+     * of the opposite sign, e.g. the conjugate of
+     * {@code 1 + POSITIVE_INFINITY i} is {@code 1 - NEGATIVE_INFINITY i}.
+     * </p>
+     * @return the conjugate of this Complex object.
+     */
+    public Complex conjugate() {
+        if (isNaN) {
+            return NaN;
+        }
+
+        return createComplex(real, -imaginary);
+    }
+
+    /**
+     * Returns a {@code Complex} whose value is
+     * {@code (this / divisor)}.
+     * Implements the definitional formula
+     * <pre>
+     *  <code>
+     *    a + bi          ac + bd + (bc - ad)i
+     *    ----------- = -------------------------
+     *    c + di         c<sup>2</sup> + d<sup>2</sup>
+     *  </code>
+     * </pre>
+     * but uses
+     * <a href="http://doi.acm.org/10.1145/1039813.1039814";>
+     * prescaling of operands</a> to limit the effects of overflows and
+     * underflows in the computation.
+     * <p>
+     * {@code Infinite} and {@code NaN} values are handled according to the
+     * following rules, applied in the order presented:
+     * <ul>
+     *  <li>If either {@code this} or {@code divisor} has a {@code NaN} value
+     *   in either part, {@link #NaN} is returned.
+     *  </li>
+     *  <li>If {@code divisor} equals {@link #ZERO}, {@link #NaN} is returned.
+     *  </li>
+     *  <li>If {@code this} and {@code divisor} are both infinite,
+     *   {@link #NaN} is returned.
+     *  </li>
+     *  <li>If {@code this} is finite (i.e., has no {@code Infinite} or
+     *   {@code NaN} parts) and {@code divisor} is infinite (one or both parts
+     *   infinite), {@link #ZERO} is returned.
+     *  </li>
+     *  <li>If {@code this} is infinite and {@code divisor} is finite,
+     *   {@code NaN} values are returned in the parts of the result if the
+     *   {@link java.lang.Double} rules applied to the definitional formula
+     *   force {@code NaN} results.
+     *  </li>
+     * </ul>
+     *
+     * @param divisor Value by which this {@code Complex} is to be divided.
+     * @return {@code this / divisor}.
+     */
+    public Complex divide(Complex divisor) {
+        checkNotNull(divisor);
+        if (isNaN || divisor.isNaN) {
+            return NaN;
+        }
+
+        final double c = divisor.getReal();
+        final double d = divisor.getImaginary();
+        if (c == 0.0 && d == 0.0) {
+            return NaN;
+        }
+
+        if (divisor.isInfinite() && !isInfinite()) {
+            return ZERO;
+        }
+
+        if (Math.abs(c) < Math.abs(d)) {
+            double q = c / d;
+            double denominator = c * q + d;
+            return createComplex((real * q + imaginary) / denominator,
+                (imaginary * q - real) / denominator);
+        } else {
+            double q = d / c;
+            double denominator = d * q + c;
+            return createComplex((imaginary * q + real) / denominator,
+                (imaginary - real * q) / denominator);
+        }
+    }
+
+    /**
+     * Returns a {@code Complex} whose value is {@code (this / divisor)},
+     * with {@code divisor} interpreted as a real number.
+     *
+     * @param  divisor Value by which this {@code Complex} is to be divided.
+     * @return {@code this / divisor}.
+     * @see #divide(Complex)
+     */
+    public Complex divide(double divisor) {
+        if (isNaN || Double.isNaN(divisor)) {
+            return NaN;
+        }
+        if (divisor == 0d) {
+            return NaN;
+        }
+        if (Double.isInfinite(divisor)) {
+            return !isInfinite() ? ZERO : NaN;
+        }
+        return createComplex(real / divisor,
+                             imaginary  / divisor);
+    }
+
+    /** {@inheritDoc} */
+    public Complex reciprocal() {
+        if (isNaN) {
+            return NaN;
+        }
+
+        if (real == 0.0 && imaginary == 0.0) {
+            return INF;
+        }
+
+        if (isInfinite) {
+            return ZERO;
+        }
+
+        if (Math.abs(real) < Math.abs(imaginary)) {
+            double q = real / imaginary;
+            double scale = 1. / (real * q + imaginary);
+            return createComplex(scale * q, -scale);
+        } else {
+            double q = imaginary / real;
+            double scale = 1. / (imaginary * q + real);
+            return createComplex(scale, -scale * q);
+        }
+    }
+
+    /**
+     * Test for equality with another object.
+     * If both the real and imaginary parts of two complex numbers
+     * are exactly the same, and neither is {@code Double.NaN}, the two
+     * Complex objects are considered to be equal.
+     * The behavior is the same as for JDK's {@link Double#equals(Object)
+     * Double}:
+     * <ul>
+     *  <li>All {@code NaN} values are considered to be equal,
+     *   i.e, if either (or both) real and imaginary parts of the complex
+     *   number are equal to {@code Double.NaN}, the complex number is equal
+     *   to {@code NaN}.
+     *  </li>
+     *  <li>
+     *   Instances constructed with different representations of zero (i.e.
+     *   either "0" or "-0") are <em>not</em> considered to be equal.
+     *  </li>
+     * </ul>
+     *
+     * @param other Object to test for equality with this instance.
+     * @return {@code true} if the objects are equal, {@code false} if object
+     * is {@code null}, not an instance of {@code Complex}, or not equal to
+     * this instance.
+     */
+    @Override
+    public boolean equals(Object other) {
+        if (this == other) {
+            return true;
+        }
+        if (other instanceof Complex){
+            Complex c = (Complex) other;
+            if (c.isNaN) {
+                return isNaN;
+            } else {
+                return equals(real, c.real) &&
+                    equals(imaginary, c.imaginary);
+            }
+        }
+        return false;
+    }
+
+    /**
+     * Test for the floating-point equality between Complex objects.
+     * It returns {@code true} if both arguments are equal or within the
+     * range of allowed error (inclusive).
+     *
+     * @param x First value (cannot be {@code null}).
+     * @param y Second value (cannot be {@code null}).
+     * @param maxUlps {@code (maxUlps - 1)} is the number of floating point
+     * values between the real (resp. imaginary) parts of {@code x} and
+     * {@code y}.
+     * @return {@code true} if there are fewer than {@code maxUlps} floating
+     * point values between the real (resp. imaginary) parts of {@code x}
+     * and {@code y}.
+     *
+     * @see Precision#equals(double,double,int)
+     * @since 3.3
+     */
+    public static boolean equals(Complex x, Complex y, int maxUlps) {
+        return Precision.equals(x.real, y.real, maxUlps) &&
+            Precision.equals(x.imaginary, y.imaginary, maxUlps);
+    }
+
+    /**
+     * Returns {@code true} iff the values are equal as defined by
+     * {@link #equals(Complex,Complex,int) equals(x, y, 1)}.
+     *
+     * @param x First value (cannot be {@code null}).
+     * @param y Second value (cannot be {@code null}).
+     * @return {@code true} if the values are equal.
+     *
+     * @since 3.3
+     */
+    public static boolean equals(Complex x, Complex y) {
+        return equals(x, y, 1);
+    }
+
+    /**
+     * Returns {@code true} if, both for the real part and for the imaginary
+     * part, there is no double value strictly between the arguments or the
+     * difference between them is within the range of allowed error
+     * (inclusive).  Returns {@code false} if either of the arguments is NaN.
+     *
+     * @param x First value (cannot be {@code null}).
+     * @param y Second value (cannot be {@code null}).
+     * @param eps Amount of allowed absolute error.
+     * @return {@code true} if the values are two adjacent floating point
+     * numbers or they are within range of each other.
+     *
+     * @see Precision#equals(double,double,double)
+     * @since 3.3
+     */
+    public static boolean equals(Complex x, Complex y, double eps) {
+        return Precision.equals(x.real, y.real, eps) &&
+            Precision.equals(x.imaginary, y.imaginary, eps);
+    }
+
+    /**
+     * Returns {@code true} if, both for the real part and for the imaginary
+     * part, there is no double value strictly between the arguments or the
+     * relative difference between them is smaller or equal to the given
+     * tolerance. Returns {@code false} if either of the arguments is NaN.
+     *
+     * @param x First value (cannot be {@code null}).
+     * @param y Second value (cannot be {@code null}).
+     * @param eps Amount of allowed relative error.
+     * @return {@code true} if the values are two adjacent floating point
+     * numbers or they are within range of each other.
+     *
+     * @see Precision#equalsWithRelativeTolerance(double,double,double)
+     * @since 3.3
+     */
+    public static boolean equalsWithRelativeTolerance(Complex x, Complex y,
+                                                      double eps) {
+        return Precision.equalsWithRelativeTolerance(x.real, y.real, eps) &&
+            Precision.equalsWithRelativeTolerance(x.imaginary, y.imaginary, 
eps);
+    }
+
+    /**
+     * Get a hashCode for the complex number.
+     * Any {@code Double.NaN} value in real or imaginary part produces
+     * the same hash code {@code 7}.
+     *
+     * @return a hash code value for this object.
+     */
+    @Override
+    public int hashCode() {
+        if (isNaN) {
+            return 7;
+        }
+        return 37 * (17 * hash(imaginary) +
+            hash(real));
+    }
+
+    /**
+     * Access the imaginary part.
+     *
+     * @return the imaginary part.
+     */
+    public double getImaginary() {
+        return imaginary;
+    }
+
+    /**
+     * Access the real part.
+     *
+     * @return the real part.
+     */
+    public double getReal() {
+        return real;
+    }
+
+    /**
+     * Checks whether either or both parts of this complex number is
+     * {@code NaN}.
+     *
+     * @return true if either or both parts of this complex number is
+     * {@code NaN}; false otherwise.
+     */
+    public boolean isNaN() {
+        return isNaN;
+    }
+
+    /**
+     * Checks whether either the real or imaginary part of this complex number
+     * takes an infinite value (either {@code Double.POSITIVE_INFINITY} or
+     * {@code Double.NEGATIVE_INFINITY}) and neither part
+     * is {@code NaN}.
+     *
+     * @return true if one or both parts of this complex number are infinite
+     * and neither part is {@code NaN}.
+     */
+    public boolean isInfinite() {
+        return isInfinite;
+    }
+
+    /**
+     * Returns a {@code Complex} whose value is {@code this * factor}.
+     * Implements preliminary checks for {@code NaN} and infinity followed by
+     * the definitional formula:
+     * <p>
+     *   {@code (a + bi)(c + di) = (ac - bd) + (ad + bc)i}
+     * </p>
+     * Returns {@link #NaN} if either {@code this} or {@code factor} has one or
+     * more {@code NaN} parts.
+     * <p>
+     * Returns {@link #INF} if neither {@code this} nor {@code factor} has one
+     * or more {@code NaN} parts and if either {@code this} or {@code factor}
+     * has one or more infinite parts (same result is returned regardless of
+     * the sign of the components).
+     * </p><p>
+     * Returns finite values in components of the result per the definitional
+     * formula in all remaining cases.</p>
+     *
+     * @param  factor value to be multiplied by this {@code Complex}.
+     * @return {@code this * factor}.
+     */
+    public Complex multiply(Complex factor) {
+        checkNotNull(factor);
+        if (isNaN || factor.isNaN) {
+            return NaN;
+        }
+        if (Double.isInfinite(real) ||
+            Double.isInfinite(imaginary) ||
+            Double.isInfinite(factor.real) ||
+            Double.isInfinite(factor.imaginary)) {
+            // we don't use isInfinite() to avoid testing for NaN again
+            return INF;
+        }
+        return createComplex(real * factor.real - imaginary * factor.imaginary,
+                             real * factor.imaginary + imaginary * 
factor.real);
+    }
+
+    /**
+     * Returns a {@code Complex} whose value is {@code this * factor}, with 
{@code factor}
+     * interpreted as a integer number.
+     *
+     * @param  factor value to be multiplied by this {@code Complex}.
+     * @return {@code this * factor}.
+     * @see #multiply(Complex)
+     */
+    public Complex multiply(final int factor) {
+        if (isNaN) {
+            return NaN;
+        }
+        if (Double.isInfinite(real) ||
+            Double.isInfinite(imaginary)) {
+            return INF;
+        }
+        return createComplex(real * factor, imaginary * factor);
+    }
+
+    /**
+     * Returns a {@code Complex} whose value is {@code this * factor}, with 
{@code factor}
+     * interpreted as a real number.
+     *
+     * @param  factor value to be multiplied by this {@code Complex}.
+     * @return {@code this * factor}.
+     * @see #multiply(Complex)
+     */
+    public Complex multiply(double factor) {
+        if (isNaN || Double.isNaN(factor)) {
+            return NaN;
+        }
+        if (Double.isInfinite(real) ||
+            Double.isInfinite(imaginary) ||
+            Double.isInfinite(factor)) {
+            // we don't use isInfinite() to avoid testing for NaN again
+            return INF;
+        }
+        return createComplex(real * factor, imaginary * factor);
+    }
+
+    /**
+     * Returns a {@code Complex} whose value is {@code (-this)}.
+     * Returns {@code NaN} if either real or imaginary
+     * part of this Complex number is {@code Double.NaN}.
+     *
+     * @return {@code -this}.
+     */
+    public Complex negate() {
+        if (isNaN) {
+            return NaN;
+        }
+
+        return createComplex(-real, -imaginary);
+    }
+
+    /**
+     * Returns a {@code Complex} whose value is
+     * {@code (this - subtrahend)}.
+     * Uses the definitional formula
+     * <p>
+     *  {@code (a + bi) - (c + di) = (a-c) + (b-d)i}
+     * </p>
+     * If either {@code this} or {@code subtrahend} has a {@code NaN]} value 
in either part,
+     * {@link #NaN} is returned; otherwise infinite and {@code NaN} values are
+     * returned in the parts of the result according to the rules for
+     * {@link java.lang.Double} arithmetic.
+     *
+     * @param  subtrahend value to be subtracted from this {@code Complex}.
+     * @return {@code this - subtrahend}.
+     */
+    public Complex subtract(Complex subtrahend) {
+        checkNotNull(subtrahend);
+        if (isNaN || subtrahend.isNaN) {
+            return NaN;
+        }
+
+        return createComplex(real - subtrahend.getReal(),
+                             imaginary - subtrahend.getImaginary());
+    }
+
+    /**
+     * Returns a {@code Complex} whose value is
+     * {@code (this - subtrahend)}.
+     *
+     * @param  subtrahend value to be subtracted from this {@code Complex}.
+     * @return {@code this - subtrahend}.
+     * @see #subtract(Complex)
+     */
+    public Complex subtract(double subtrahend) {
+        if (isNaN || Double.isNaN(subtrahend)) {
+            return NaN;
+        }
+        return createComplex(real - subtrahend, imaginary);
+    }
+
+    /**
+     * Compute the
+     * <a href="http://mathworld.wolfram.com/InverseCosine.html"; TARGET="_top">
+     * inverse cosine</a> of this complex number.
+     * Implements the formula:
+     * <p>
+     *  {@code acos(z) = -i (log(z + i (sqrt(1 - z<sup>2</sup>))))}
+     * </p>
+     * Returns {@link Complex#NaN} if either real or imaginary part of the
+     * input argument is {@code NaN} or infinite.
+     *
+     * @return the inverse cosine of this complex number.
+     * @since 1.2
+     */
+    public Complex acos() {
+        if (isNaN) {
+            return NaN;
+        }
+
+        return this.add(this.sqrt1z().multiply(I)).log().multiply(I.negate());
+    }
+
+    /**
+     * Compute the
+     * <a href="http://mathworld.wolfram.com/InverseSine.html"; TARGET="_top">
+     * inverse sine</a> of this complex number.
+     * Implements the formula:
+     * <p>
+     *  {@code asin(z) = -i (log(sqrt(1 - z<sup>2</sup>) + iz))}
+     * </p><p>
+     * Returns {@link Complex#NaN} if either real or imaginary part of the
+     * input argument is {@code NaN} or infinite.</p>
+     *
+     * @return the inverse sine of this complex number.
+     * @since 1.2
+     */
+    public Complex asin() {
+        if (isNaN) {
+            return NaN;
+        }
+
+        return sqrt1z().add(this.multiply(I)).log().multiply(I.negate());
+    }
+
+    /**
+     * Compute the
+     * <a href="http://mathworld.wolfram.com/InverseTangent.html"; 
TARGET="_top">
+     * inverse tangent</a> of this complex number.
+     * Implements the formula:
+     * <p>
+     * {@code atan(z) = (i/2) log((i + z)/(i - z))}
+     * </p><p>
+     * Returns {@link Complex#NaN} if either real or imaginary part of the
+     * input argument is {@code NaN} or infinite.</p>
+     *
+     * @return the inverse tangent of this complex number
+     * @since 1.2
+     */
+    public Complex atan() {
+        if (isNaN) {
+            return NaN;
+        }
+
+        return this.add(I).divide(I.subtract(this)).log()
+                .multiply(I.divide(createComplex(2.0, 0.0)));
+    }
+
+    /**
+     * Compute the
+     * <a href="http://mathworld.wolfram.com/Cosine.html"; TARGET="_top">
+     * cosine</a> of this complex number.
+     * Implements the formula:
+     * <p>
+     *  {@code cos(a + bi) = cos(a)cosh(b) - sin(a)sinh(b)i}
+     * </p><p>
+     * where the (real) functions on the right-hand side are
+     * {@link Math#sin}, {@link Math#cos},
+     * {@link Math#cosh} and {@link Math#sinh}.
+     * </p><p>
+     * Returns {@link Complex#NaN} if either real or imaginary part of the
+     * input argument is {@code NaN}.
+     * </p><p>
+     * Infinite values in real or imaginary parts of the input may result in
+     * infinite or NaN values returned in parts of the result.</p>
+     * <pre>
+     *  Examples:
+     *  <code>
+     *   cos(1 &plusmn; INFINITY i) = 1 \u2213 INFINITY i
+     *   cos(&plusmn;INFINITY + i) = NaN + NaN i
+     *   cos(&plusmn;INFINITY &plusmn; INFINITY i) = NaN + NaN i
+     *  </code>
+     * </pre>
+     *
+     * @return the cosine of this complex number.
+     * @since 1.2
+     */
+    public Complex cos() {
+        if (isNaN) {
+            return NaN;
+        }
+
+        return createComplex(Math.cos(real) * Math.cosh(imaginary),
+                             -Math.sin(real) * Math.sinh(imaginary));
+    }
+
+    /**
+     * Compute the
+     * <a href="http://mathworld.wolfram.com/HyperbolicCosine.html"; 
TARGET="_top">
+     * hyperbolic cosine</a> of this complex number.
+     * Implements the formula:
+     * <pre>
+     *  <code>
+     *   cosh(a + bi) = cosh(a)cos(b) + sinh(a)sin(b)i
+     *  </code>
+     * </pre>
+     * where the (real) functions on the right-hand side are
+     * {@link Math#sin}, {@link Math#cos},
+     * {@link Math#cosh} and {@link Math#sinh}.
+     * <p>
+     * Returns {@link Complex#NaN} if either real or imaginary part of the
+     * input argument is {@code NaN}.
+     * </p>
+     * Infinite values in real or imaginary parts of the input may result in
+     * infinite or NaN values returned in parts of the result.
+     * <pre>
+     *  Examples:
+     *  <code>
+     *   cosh(1 &plusmn; INFINITY i) = NaN + NaN i
+     *   cosh(&plusmn;INFINITY + i) = INFINITY &plusmn; INFINITY i
+     *   cosh(&plusmn;INFINITY &plusmn; INFINITY i) = NaN + NaN i
+     *  </code>
+     * </pre>
+     *
+     * @return the hyperbolic cosine of this complex number.
+     * @since 1.2
+     */
+    public Complex cosh() {
+        if (isNaN) {
+            return NaN;
+        }
+
+        return createComplex(Math.cosh(real) * Math.cos(imaginary),
+                             Math.sinh(real) * Math.sin(imaginary));
+    }
+
+    /**
+     * Compute the
+     * <a href="http://mathworld.wolfram.com/ExponentialFunction.html"; 
TARGET="_top">
+     * exponential function</a> of this complex number.
+     * Implements the formula:
+     * <pre>
+     *  <code>
+     *   exp(a + bi) = exp(a)cos(b) + exp(a)sin(b)i
+     *  </code>
+     * </pre>
+     * where the (real) functions on the right-hand side are
+     * {@link Math#exp}, {@link Math#cos}, and
+     * {@link Math#sin}.
+     * <p>
+     * Returns {@link Complex#NaN} if either real or imaginary part of the
+     * input argument is {@code NaN}.
+     * </p>
+     * Infinite values in real or imaginary parts of the input may result in
+     * infinite or NaN values returned in parts of the result.
+     * <pre>
+     *  Examples:
+     *  <code>
+     *   exp(1 &plusmn; INFINITY i) = NaN + NaN i
+     *   exp(INFINITY + i) = INFINITY + INFINITY i
+     *   exp(-INFINITY + i) = 0 + 0i
+     *   exp(&plusmn;INFINITY &plusmn; INFINITY i) = NaN + NaN i
+     *  </code>
+     * </pre>
+     *
+     * @return <code><i>e</i><sup>this</sup></code>.
+     * @since 1.2
+     */
+    public Complex exp() {
+        if (isNaN) {
+            return NaN;
+        }
+
+        double expReal = Math.exp(real);
+        return createComplex(expReal *  Math.cos(imaginary),
+                             expReal * Math.sin(imaginary));
+    }
+
+    /**
+     * Compute the
+     * <a href="http://mathworld.wolfram.com/NaturalLogarithm.html"; 
TARGET="_top">
+     * natural logarithm</a> of this complex number.
+     * Implements the formula:
+     * <pre>
+     *  <code>
+     *   log(a + bi) = ln(|a + bi|) + arg(a + bi)i
+     *  </code>
+     * </pre>
+     * where ln on the right hand side is {@link Math#log},
+     * {@code |a + bi|} is the modulus, {@link Complex#abs},  and
+     * {@code arg(a + bi) = }{@link Math#atan2}(b, a).
+     * <p>
+     * Returns {@link Complex#NaN} if either real or imaginary part of the
+     * input argument is {@code NaN}.
+     * </p>
+     * Infinite (or critical) values in real or imaginary parts of the input 
may
+     * result in infinite or NaN values returned in parts of the result.
+     * <pre>
+     *  Examples:
+     *  <code>
+     *   log(1 &plusmn; INFINITY i) = INFINITY &plusmn; (&pi;/2)i
+     *   log(INFINITY + i) = INFINITY + 0i
+     *   log(-INFINITY + i) = INFINITY + &pi;i
+     *   log(INFINITY &plusmn; INFINITY i) = INFINITY &plusmn; (&pi;/4)i
+     *   log(-INFINITY &plusmn; INFINITY i) = INFINITY &plusmn; (3&pi;/4)i
+     *   log(0 + 0i) = -INFINITY + 0i
+     *  </code>
+     * </pre>
+     *
+     * @return the value <code>ln &nbsp; this</code>, the natural logarithm
+     * of {@code this}.
+     * @since 1.2
+     */
+    public Complex log() {
+        if (isNaN) {
+            return NaN;
+        }
+
+        return createComplex(Math.log(abs()),
+                             Math.atan2(imaginary, real));
+    }
+
+    /**
+     * Returns of value of this complex number raised to the power of {@code 
x}.
+     * Implements the formula:
+     * <pre>
+     *  <code>
+     *   y<sup>x</sup> = exp(x&middot;log(y))
+     *  </code>
+     * </pre>
+     * where {@code exp} and {@code log} are {@link #exp} and
+     * {@link #log}, respectively.
+     * <p>
+     * Returns {@link Complex#NaN} if either real or imaginary part of the
+     * input argument is {@code NaN} or infinite, or if {@code y}
+     * equals {@link Complex#ZERO}.</p>
+     *
+     * @param  x exponent to which this {@code Complex} is to be raised.
+     * @return <code> this<sup>x</sup></code>.
+     * @since 1.2
+     */
+    public Complex pow(Complex x) {
+        checkNotNull(x);
+        if (real == 0 && imaginary == 0) {
+            if (x.real > 0 && x.imaginary == 0) {
+                // 0 raised to positive number is 0
+                return ZERO;
+            } else {
+                // 0 raised to anything else is NaN
+                return NaN;
+            }
+        }
+        return this.log().multiply(x).exp();
+    }
+
+    /**
+     * Returns of value of this complex number raised to the power of {@code 
x}.
+     *
+     * @param  x exponent to which this {@code Complex} is to be raised.
+     * @return <code>this<sup>x</sup></code>.
+     * @see #pow(Complex)
+     */
+     public Complex pow(double x) {
+        if (real == 0 && imaginary == 0) {
+            if (x > 0) {
+                // 0 raised to positive number is 0
+                return ZERO;
+            } else {
+                // 0 raised to anything else is NaN
+                return NaN;
+            }
+        }
+        return this.log().multiply(x).exp();
+    }
+
+    /**
+     * Compute the
+     * <a href="http://mathworld.wolfram.com/Sine.html"; TARGET="_top">
+     * sine</a>
+     * of this complex number.
+     * Implements the formula:
+     * <pre>
+     *  <code>
+     *   sin(a + bi) = sin(a)cosh(b) - cos(a)sinh(b)i
+     *  </code>
+     * </pre>
+     * where the (real) functions on the right-hand side are
+     * {@link Math#sin}, {@link Math#cos},
+     * {@link Math#cosh} and {@link Math#sinh}.
+     * <p>
+     * Returns {@link Complex#NaN} if either real or imaginary part of the
+     * input argument is {@code NaN}.
+     * </p><p>
+     * Infinite values in real or imaginary parts of the input may result in
+     * infinite or {@code NaN} values returned in parts of the result.
+     * <pre>
+     *  Examples:
+     *  <code>
+     *   sin(1 &plusmn; INFINITY i) = 1 &plusmn; INFINITY i
+     *   sin(&plusmn;INFINITY + i) = NaN + NaN i
+     *   sin(&plusmn;INFINITY &plusmn; INFINITY i) = NaN + NaN i
+     *  </code>
+     * </pre>
+     *
+     * @return the sine of this complex number.
+     * @since 1.2
+     */
+    public Complex sin() {
+        if (isNaN) {
+            return NaN;
+        }
+
+        return createComplex(Math.sin(real) * Math.cosh(imaginary),
+                             Math.cos(real) * Math.sinh(imaginary));
+    }
+
+    /**
+     * Compute the
+     * <a href="http://mathworld.wolfram.com/HyperbolicSine.html"; 
TARGET="_top">
+     * hyperbolic sine</a> of this complex number.
+     * Implements the formula:
+     * <pre>
+     *  <code>
+     *   sinh(a + bi) = sinh(a)cos(b)) + cosh(a)sin(b)i
+     *  </code>
+     * </pre>
+     * where the (real) functions on the right-hand side are
+     * {@link Math#sin}, {@link Math#cos},
+     * {@link Math#cosh} and {@link Math#sinh}.
+     * <p>
+     * Returns {@link Complex#NaN} if either real or imaginary part of the
+     * input argument is {@code NaN}.
+     * </p><p>
+     * Infinite values in real or imaginary parts of the input may result in
+     * infinite or NaN values returned in parts of the result.
+     * <pre>
+     *  Examples:
+     *  <code>
+     *   sinh(1 &plusmn; INFINITY i) = NaN + NaN i
+     *   sinh(&plusmn;INFINITY + i) = &plusmn; INFINITY + INFINITY i
+     *   sinh(&plusmn;INFINITY &plusmn; INFINITY i) = NaN + NaN i
+     *  </code>
+     * </pre>
+     *
+     * @return the hyperbolic sine of {@code this}.
+     * @since 1.2
+     */
+    public Complex sinh() {
+        if (isNaN) {
+            return NaN;
+        }
+
+        return createComplex(Math.sinh(real) * Math.cos(imaginary),
+            Math.cosh(real) * Math.sin(imaginary));
+    }
+
+    /**
+     * Compute the
+     * <a href="http://mathworld.wolfram.com/SquareRoot.html"; TARGET="_top">
+     * square root</a> of this complex number.
+     * Implements the following algorithm to compute {@code sqrt(a + bi)}:
+     * <ol><li>Let {@code t = sqrt((|a| + |a + bi|) / 2)}</li>
+     * <li><pre>if {@code  a &#8805; 0} return {@code t + (b/2t)i}
+     *  else return {@code |b|/2t + sign(b)t i }</pre></li>
+     * </ol>
+     * where <ul>
+     * <li>{@code |a| = }{@link Math#abs}(a)</li>
+     * <li>{@code |a + bi| = }{@link Complex#abs}(a + bi)</li>
+     * <li>{@code sign(b) =  }{@link Math#copySign(double,double) copySign(1d, 
b)}
+     * </ul>
+     * <p>
+     * Returns {@link Complex#NaN} if either real or imaginary part of the
+     * input argument is {@code NaN}.
+     * </p>
+     * Infinite values in real or imaginary parts of the input may result in
+     * infinite or NaN values returned in parts of the result.
+     * <pre>
+     *  Examples:
+     *  <code>
+     *   sqrt(1 &plusmn; INFINITY i) = INFINITY + NaN i
+     *   sqrt(INFINITY + i) = INFINITY + 0i
+     *   sqrt(-INFINITY + i) = 0 + INFINITY i
+     *   sqrt(INFINITY &plusmn; INFINITY i) = INFINITY + NaN i
+     *   sqrt(-INFINITY &plusmn; INFINITY i) = NaN &plusmn; INFINITY i
+     *  </code>
+     * </pre>
+     *
+     * @return the square root of {@code this}.
+     * @since 1.2
+     */
+    public Complex sqrt() {
+        if (isNaN) {
+            return NaN;
+        }
+
+        if (real == 0.0 && imaginary == 0.0) {
+            return createComplex(0.0, 0.0);
+        }
+
+        double t = Math.sqrt((Math.abs(real) + abs()) / 2.0);
+        if (real >= 0.0) {
+            return createComplex(t, imaginary / (2.0 * t));
+        } else {
+            return createComplex(Math.abs(imaginary) / (2.0 * t),
+                                 Math.copySign(1d, imaginary) * t);
+        }
+    }
+
+    /**
+     * Compute the
+     * <a href="http://mathworld.wolfram.com/SquareRoot.html"; TARGET="_top">
+     * square root</a> of <code>1 - this<sup>2</sup></code> for this complex
+     * number.
+     * Computes the result directly as
+     * {@code sqrt(ONE.subtract(z.multiply(z)))}.
+     * <p>
+     * Returns {@link Complex#NaN} if either real or imaginary part of the
+     * input argument is {@code NaN}.
+     * </p>
+     * Infinite values in real or imaginary parts of the input may result in
+     * infinite or NaN values returned in parts of the result.
+     *
+     * @return the square root of <code>1 - this<sup>2</sup></code>.
+     * @since 1.2
+     */
+    public Complex sqrt1z() {
+        return createComplex(1.0, 0.0).subtract(this.multiply(this)).sqrt();
+    }
+
+    /**
+     * Compute the
+     * <a href="http://mathworld.wolfram.com/Tangent.html"; TARGET="_top">
+     * tangent</a> of this complex number.
+     * Implements the formula:
+     * <pre>
+     *  <code>
+     *   tan(a + bi) = sin(2a)/(cos(2a)+cosh(2b)) + 
[sinh(2b)/(cos(2a)+cosh(2b))]i
+     *  </code>
+     * </pre>
+     * where the (real) functions on the right-hand side are
+     * {@link Math#sin}, {@link Math#cos}, {@link Math#cosh} and
+     * {@link Math#sinh}.
+     * <p>
+     * Returns {@link Complex#NaN} if either real or imaginary part of the
+     * input argument is {@code NaN}.
+     * </p>
+     * Infinite (or critical) values in real or imaginary parts of the input 
may
+     * result in infinite or NaN values returned in parts of the result.
+     * <pre>
+     *  Examples:
+     *  <code>
+     *   tan(a &plusmn; INFINITY i) = 0 &plusmn; i
+     *   tan(&plusmn;INFINITY + bi) = NaN + NaN i
+     *   tan(&plusmn;INFINITY &plusmn; INFINITY i) = NaN + NaN i
+     *   tan(&plusmn;&pi;/2 + 0 i) = &plusmn;INFINITY + NaN i
+     *  </code>
+     * </pre>
+     *
+     * @return the tangent of {@code this}.
+     * @since 1.2
+     */
+    public Complex tan() {
+        if (isNaN || Double.isInfinite(real)) {
+            return NaN;
+        }
+        if (imaginary > 20.0) {
+            return createComplex(0.0, 1.0);
+        }
+        if (imaginary < -20.0) {
+            return createComplex(0.0, -1.0);
+        }
+
+        double real2 = 2.0 * real;
+        double imaginary2 = 2.0 * imaginary;
+        double d = Math.cos(real2) + Math.cosh(imaginary2);
+
+        return createComplex(Math.sin(real2) / d,
+                             Math.sinh(imaginary2) / d);
+    }
+
+    /**
+     * Compute the
+     * <a href="http://mathworld.wolfram.com/HyperbolicTangent.html"; 
TARGET="_top">
+     * hyperbolic tangent</a> of this complex number.
+     * Implements the formula:
+     * <pre>
+     *  <code>
+     *   tan(a + bi) = sinh(2a)/(cosh(2a)+cos(2b)) + 
[sin(2b)/(cosh(2a)+cos(2b))]i
+     *  </code>
+     * </pre>
+     * where the (real) functions on the right-hand side are
+     * {@link Math#sin}, {@link Math#cos}, {@link Math#cosh} and
+     * {@link Math#sinh}.
+     * <p>
+     * Returns {@link Complex#NaN} if either real or imaginary part of the
+     * input argument is {@code NaN}.
+     * </p>
+     * Infinite values in real or imaginary parts of the input may result in
+     * infinite or NaN values returned in parts of the result.
+     * <pre>
+     *  Examples:
+     *  <code>
+     *   tanh(a &plusmn; INFINITY i) = NaN + NaN i
+     *   tanh(&plusmn;INFINITY + bi) = &plusmn;1 + 0 i
+     *   tanh(&plusmn;INFINITY &plusmn; INFINITY i) = NaN + NaN i
+     *   tanh(0 + (&pi;/2)i) = NaN + INFINITY i
+     *  </code>
+     * </pre>
+     *
+     * @return the hyperbolic tangent of {@code this}.
+     * @since 1.2
+     */
+    public Complex tanh() {
+        if (isNaN || Double.isInfinite(imaginary)) {
+            return NaN;
+        }
+        if (real > 20.0) {
+            return createComplex(1.0, 0.0);
+        }
+        if (real < -20.0) {
+            return createComplex(-1.0, 0.0);
+        }
+        double real2 = 2.0 * real;
+        double imaginary2 = 2.0 * imaginary;
+        double d = Math.cosh(real2) + Math.cos(imaginary2);
+
+        return createComplex(Math.sinh(real2) / d,
+                             Math.sin(imaginary2) / d);
+    }
+
+
+
+    /**
+     * Compute the argument of this complex number.
+     * The argument is the angle phi between the positive real axis and
+     * the point representing this number in the complex plane.
+     * The value returned is between -PI (not inclusive)
+     * and PI (inclusive), with negative values returned for numbers with
+     * negative imaginary parts.
+     * <p>
+     * If either real or imaginary part (or both) is NaN, NaN is returned.
+     * Infinite parts are handled as {@code Math.atan2} handles them,
+     * essentially treating finite parts as zero in the presence of an
+     * infinite coordinate and returning a multiple of pi/4 depending on
+     * the signs of the infinite parts.
+     * See the javadoc for {@code Math.atan2} for full details.
+     *
+     * @return the argument of {@code this}.
+     */
+    public double getArgument() {
+        return Math.atan2(getImaginary(), getReal());
+    }
+
+    /**
+     * Computes the n-th roots of this complex number.
+     * The nth roots are defined by the formula:
+     * <pre>
+     *  <code>
+     *   z<sub>k</sub> = abs<sup>1/n</sup> (cos(phi + 2&pi;k/n) + i (sin(phi + 
2&pi;k/n))
+     *  </code>
+     * </pre>
+     * for <i>{@code k=0, 1, ..., n-1}</i>, where {@code abs} and {@code phi}
+     * are respectively the {@link #abs() modulus} and
+     * {@link #getArgument() argument} of this complex number.
+     * <p>
+     * If one or both parts of this complex number is NaN, a list with just
+     * one element, {@link #NaN} is returned.
+     * if neither part is NaN, but at least one part is infinite, the result
+     * is a one-element list containing {@link #INF}.
+     *
+     * @param n Degree of root.
+     * @return a List of all {@code n}-th roots of {@code this}.
+     * @since 2.0
+     */
+    public List<Complex> nthRoot(int n) {
+
+        if (n <= 0) {
+            throw new RuntimeException("cannot compute nth root for null or 
negative n: {0}");
+        }
+
+        final List<Complex> result = new ArrayList<Complex>();
+
+        if (isNaN) {
+            result.add(NaN);
+            return result;
+        }
+        if (isInfinite()) {
+            result.add(INF);
+            return result;
+        }
+
+        // nth root of abs -- faster / more accurate to use a solver here?
+        final double nthRootOfAbs = Math.pow(abs(), 1.0 / n);
+
+        // Compute nth roots of complex number with k = 0, 1, ... n-1
+        final double nthPhi = getArgument() / n;
+        final double slice = 2 * Math.PI / n;
+        double innerPart = nthPhi;
+        for (int k = 0; k < n ; k++) {
+            // inner part
+            final double realPart = nthRootOfAbs *  Math.cos(innerPart);
+            final double imaginaryPart = nthRootOfAbs *  Math.sin(innerPart);
+            result.add(createComplex(realPart, imaginaryPart));
+            innerPart += slice;
+        }
+
+        return result;
+    }
+
+    /**
+     * Create a complex number given the real and imaginary parts.
+     *
+     * @param realPart Real part.
+     * @param imaginaryPart Imaginary part.
+     * @return a new complex number instance.
+     * @since 1.2
+     * @see #valueOf(double, double)
+     */
+    protected Complex createComplex(double realPart,
+                                    double imaginaryPart) {
+        return new Complex(realPart, imaginaryPart);
+    }
+
+    /**
+     * Create a complex number given the real and imaginary parts.
+     *
+     * @param realPart Real part.
+     * @param imaginaryPart Imaginary part.
+     * @return a Complex instance.
+     */
+    public static Complex valueOf(double realPart,
+                                  double imaginaryPart) {
+        if (Double.isNaN(realPart) ||
+            Double.isNaN(imaginaryPart)) {
+            return NaN;
+        }
+        return new Complex(realPart, imaginaryPart);
+    }
+
+    /**
+     * Create a complex number given only the real part.
+     *
+     * @param realPart Real part.
+     * @return a Complex instance.
+     */
+    public static Complex valueOf(double realPart) {
+        if (Double.isNaN(realPart)) {
+            return NaN;
+        }
+        return new Complex(realPart);
+    }
+
+    /**
+     * Resolve the transient fields in a deserialized Complex Object.
+     * Subclasses will need to override {@link #createComplex} to
+     * deserialize properly.
+     *
+     * @return A Complex instance with all fields resolved.
+     * @since 2.0
+     */
+    protected final Object readResolve() {
+        return createComplex(real, imaginary);
+    }
+
+    /** {@inheritDoc} */
+    @Override
+    public String toString() {
+        return "(" + real + ", " + imaginary + ")";
+    }
+
+       /**
+        * Checks that an object is not null.
+        *
+        * @param o Object to be checked.
+        */
+       private static void checkNotNull(Object o) {
+           if (o == null) {
+               throw new RuntimeException("Null Argument to Complex Method");
+           }
+       }
+
+       /**
+        * Returns {@code true} if the values are equal according to semantics 
of
+        * {@link Double#equals(Object)}.
+        *
+        * @param x Value
+        * @param y Value
+        * @return {@code new Double(x).equals(new Double(y))}
+        */
+       private static boolean equals(double x, double y) {
+           return new Double(x).equals(new Double(y));
+       }
+
+       /**
+     * Returns {@code true} if there is no double value strictly between the
+     * arguments or the difference between them is within the range of allowed
+     * error (inclusive). Returns {@code false} if either of the arguments
+     * is NaN.
+     *
+     * @param x First value.
+     * @param y Second value.
+     * @param eps Amount of allowed absolute error.
+     * @return {@code true} if the values are two adjacent floating point
+     * numbers or they are within range of each other.
+     */
+    public static boolean equals(double x, double y, double eps) {
+        return equals(x, y, 1) || Math.abs(y - x) <= eps;
+    }
+
+
+    /**
+     * Returns {@code true} if there is no double value strictly between the
+     * arguments or the relative difference between them is less than or equal
+     * to the given tolerance. Returns {@code false} if either of the arguments
+     * is NaN.
+     *
+     * @param x First value.
+     * @param y Second value.
+     * @param eps Amount of allowed relative error.
+     * @return {@code true} if the values are two adjacent floating point
+     * numbers or they are within range of each other.
+     * @since 3.1
+     */
+    public static boolean equalsWithRelativeTolerance(double x, double y, 
double eps) {
+        if (equals(x, y, 1)) {
+            return true;
+        }
+
+        final double absoluteMax = Math.max(Math.abs(x), Math.abs(y));
+        final double relativeDifference = Math.abs((x - y) / absoluteMax);
+
+        return relativeDifference <= eps;
+    }
+
+    /**
+     * Returns an integer hash code representing the given double value.
+     *
+     * @param value the value to be hashed
+     * @return the hash code
+     */
+    public static int hash(double value) {
+        return new Double(value).hashCode();
+    }
+
+}
+

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