SecondWatsonEstimate.java

  1. package org.drip.sample.bessel;

  2. import org.drip.numerical.common.FormatUtil;
  3. import org.drip.service.env.EnvManager;
  4. import org.drip.specialfunction.bessel.SecondWatsonIntegralEstimator;
  5. import org.drip.specialfunction.definition.BesselSecondKindEstimator;

  6. /*
  7.  * -*- mode: java; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*-
  8.  */

  9. /*!
  10.  * Copyright (C) 2020 Lakshmi Krishnamurthy
  11.  * Copyright (C) 2019 Lakshmi Krishnamurthy
  12.  *
  13.  *  This file is part of DROP, an open-source library targeting analytics/risk, transaction cost analytics,
  14.  *      asset liability management analytics, capital, exposure, and margin analytics, valuation adjustment
  15.  *      analytics, and portfolio construction analytics within and across fixed income, credit, commodity,
  16.  *      equity, FX, and structured products. It also includes auxiliary libraries for algorithm support,
  17.  *      numerical analysis, numerical optimization, spline builder, model validation, statistical learning,
  18.  *      and computational support.
  19.  *  
  20.  *      https://lakshmidrip.github.io/DROP/
  21.  *  
  22.  *  DROP is composed of three modules:
  23.  *  
  24.  *  - DROP Product Core - https://lakshmidrip.github.io/DROP-Product-Core/
  25.  *  - DROP Portfolio Core - https://lakshmidrip.github.io/DROP-Portfolio-Core/
  26.  *  - DROP Computational Core - https://lakshmidrip.github.io/DROP-Computational-Core/
  27.  *
  28.  *  DROP Product Core implements libraries for the following:
  29.  *  - Fixed Income Analytics
  30.  *  - Loan Analytics
  31.  *  - Transaction Cost Analytics
  32.  *
  33.  *  DROP Portfolio Core implements libraries for the following:
  34.  *  - Asset Allocation Analytics
  35.  *  - Asset Liability Management Analytics
  36.  *  - Capital Estimation Analytics
  37.  *  - Exposure Analytics
  38.  *  - Margin Analytics
  39.  *  - XVA Analytics
  40.  *
  41.  *  DROP Computational Core implements libraries for the following:
  42.  *  - Algorithm Support
  43.  *  - Computation Support
  44.  *  - Function Analysis
  45.  *  - Model Validation
  46.  *  - Numerical Analysis
  47.  *  - Numerical Optimizer
  48.  *  - Spline Builder
  49.  *  - Statistical Learning
  50.  *
  51.  *  Documentation for DROP is Spread Over:
  52.  *
  53.  *  - Main                     => https://lakshmidrip.github.io/DROP/
  54.  *  - Wiki                     => https://github.com/lakshmiDRIP/DROP/wiki
  55.  *  - GitHub                   => https://github.com/lakshmiDRIP/DROP
  56.  *  - Repo Layout Taxonomy     => https://github.com/lakshmiDRIP/DROP/blob/master/Taxonomy.md
  57.  *  - Javadoc                  => https://lakshmidrip.github.io/DROP/Javadoc/index.html
  58.  *  - Technical Specifications => https://github.com/lakshmiDRIP/DROP/tree/master/Docs/Internal
  59.  *  - Release Versions         => https://lakshmidrip.github.io/DROP/version.html
  60.  *  - Community Credits        => https://lakshmidrip.github.io/DROP/credits.html
  61.  *  - Issues Catalog           => https://github.com/lakshmiDRIP/DROP/issues
  62.  *  - JUnit                    => https://lakshmidrip.github.io/DROP/junit/index.html
  63.  *  - Jacoco                   => https://lakshmidrip.github.io/DROP/jacoco/index.html
  64.  *
  65.  *  Licensed under the Apache License, Version 2.0 (the "License");
  66.  *      you may not use this file except in compliance with the License.
  67.  *  
  68.  *  You may obtain a copy of the License at
  69.  *      http://www.apache.org/licenses/LICENSE-2.0
  70.  *  
  71.  *  Unless required by applicable law or agreed to in writing, software
  72.  *      distributed under the License is distributed on an "AS IS" BASIS,
  73.  *      WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  74.  *  
  75.  *  See the License for the specific language governing permissions and
  76.  *      limitations under the License.
  77.  */

  78. /**
  79.  * <i>SecondWatsonEstimate</i> illustrates the Watson Integral Based Estimation for the Cylindrical Bessel
  80.  * Function of the Second Kind for Integer Orders. The References are:
  81.  *
  82.  * <br><br>
  83.  *  <ul>
  84.  *      <li>
  85.  *          Abramowitz, M., and I. A. Stegun (2007): <i>Handbook of Mathematics Functions</i> <b>Dover Book
  86.  *              on Mathematics</b>
  87.  *      </li>
  88.  *      <li>
  89.  *          Arfken, G. B., and H. J. Weber (2005): <i>Mathematical Methods for Physicists 6<sup>th</sup>
  90.  *              Edition</i> <b>Harcourt</b> San Diego
  91.  *      </li>
  92.  *      <li>
  93.  *          Temme N. M. (1996): <i>Special Functions: An Introduction to the Classical Functions of
  94.  *              Mathematical Physics 2<sup>nd</sup> Edition</i> <b>Wiley</b> New York
  95.  *      </li>
  96.  *      <li>
  97.  *          Watson, G. N. (1995): <i>A Treatise on the Theory of Bessel Functions</i> <b>Cambridge University
  98.  *              Press</b>
  99.  *      </li>
  100.  *      <li>
  101.  *          Wikipedia (2019): Bessel Function https://en.wikipedia.org/wiki/Bessel_function
  102.  *      </li>
  103.  *  </ul>
  104.  *
  105.  *  <br><br>
  106.  *  <ul>
  107.  *      <li><b>Module </b> = <a href = "https://github.com/lakshmiDRIP/DROP/tree/master/ComputationalCore.md">Computational Core Module</a></li>
  108.  *      <li><b>Library</b> = <a href = "https://github.com/lakshmiDRIP/DROP/tree/master/FunctionAnalysisLibrary.md">Function Analysis Library</a></li>
  109.  *      <li><b>Project</b> = <a href = "https://github.com/lakshmiDRIP/DROP/tree/master/src/main/java/org/drip/sample/README.md">DROP API Construction and Usage</a></li>
  110.  *      <li><b>Package</b> = <a href = "https://github.com/lakshmiDRIP/DROP/tree/master/src/main/java/org/drip/sample/bessel/README.md">Estimates of the Bessel Functions</a></li>
  111.  *  </ul>
  112.  *
  113.  * @author Lakshmi Krishnamurthy
  114.  */

  115. public class SecondWatsonEstimate
  116. {

  117.     private static final void BesselY (
  118.         final BesselSecondKindEstimator besselSecondKindEstimator,
  119.         final int quadratureCount,
  120.         final double[] zArray,
  121.         final double[] alphaArray)
  122.         throws Exception
  123.     {
  124.         System.out.println ("\t|----------------------------------------------------------------------||");

  125.         System.out.println ("\t|           BESSEL SECOND KIND WATSON INTEGER FORM ESTIMATE            ||");

  126.         System.out.println ("\t|----------------------------------------------------------------------||");

  127.         System.out.println ("\t|    Quadrature Term Count => " + quadratureCount);

  128.         System.out.println ("\t|----------------------------------------------------------------------||");

  129.         System.out.println ("\t|        L -> R:                                                       ||");

  130.         System.out.println ("\t|                - z                                                   ||");

  131.         System.out.println ("\t|                - Alpha Bessel Estimate Row                           ||");

  132.         System.out.println ("\t|----------------------------------------------------------------------||");

  133.         for (double z : zArray)
  134.         {
  135.             String display = "\t| [" + FormatUtil.FormatDouble (z, 2, 1, 1., false) + "] => ";

  136.             for (double alpha : alphaArray)
  137.             {
  138.                 display = display + " " + FormatUtil.FormatDouble (
  139.                     besselSecondKindEstimator.bigY (
  140.                         alpha,
  141.                         z
  142.                     ), 1, 6, 1.
  143.                 ) + " |";
  144.             }

  145.             System.out.println (display + "|");
  146.         }

  147.         System.out.println ("\t|----------------------------------------------------------------------||");

  148.         System.out.println();
  149.     }

  150.     public static final void main (
  151.         final String[] argumentArray)
  152.         throws Exception
  153.     {
  154.         EnvManager.InitEnv ("");

  155.         int[] quadratureCountArray =
  156.         {
  157.             25,
  158.             50,
  159.             75,
  160.         };
  161.         double[] zArray =
  162.         {
  163.              1.,
  164.              2.,
  165.              3.,
  166.              4.,
  167.              5.,
  168.              6.,
  169.              7.,
  170.              8.,
  171.              9.,
  172.             10.,
  173.             11.,
  174.             12.,
  175.             13.,
  176.             14.,
  177.             15.,
  178.             16.,
  179.             17.,
  180.             18.,
  181.             19.,
  182.             20.,
  183.         };
  184.         double[] alphaArray =
  185.         {
  186.             0.0,
  187.             1.0,
  188.             2.0,
  189.             3.0,
  190.             4.0,
  191.         };

  192.         for (int quadratureCount : quadratureCountArray)
  193.         {
  194.             BesselY (
  195.                 SecondWatsonIntegralEstimator.IntegerForm (quadratureCount),
  196.                 quadratureCount,
  197.                 zArray,
  198.                 alphaArray
  199.             );
  200.         }

  201.         EnvManager.TerminateEnv();
  202.     }
  203. }