Kummer24.java

  1. package org.drip.specialfunction.group;

  2. /*
  3.  * -*- mode: java; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*-
  4.  */

  5. /*!
  6.  * Copyright (C) 2020 Lakshmi Krishnamurthy
  7.  * Copyright (C) 2019 Lakshmi Krishnamurthy
  8.  *
  9.  *  This file is part of DROP, an open-source library targeting analytics/risk, transaction cost analytics,
  10.  *      asset liability management analytics, capital, exposure, and margin analytics, valuation adjustment
  11.  *      analytics, and portfolio construction analytics within and across fixed income, credit, commodity,
  12.  *      equity, FX, and structured products. It also includes auxiliary libraries for algorithm support,
  13.  *      numerical analysis, numerical optimization, spline builder, model validation, statistical learning,
  14.  *      and computational support.
  15.  *  
  16.  *      https://lakshmidrip.github.io/DROP/
  17.  *  
  18.  *  DROP is composed of three modules:
  19.  *  
  20.  *  - DROP Product Core - https://lakshmidrip.github.io/DROP-Product-Core/
  21.  *  - DROP Portfolio Core - https://lakshmidrip.github.io/DROP-Portfolio-Core/
  22.  *  - DROP Computational Core - https://lakshmidrip.github.io/DROP-Computational-Core/
  23.  *
  24.  *  DROP Product Core implements libraries for the following:
  25.  *  - Fixed Income Analytics
  26.  *  - Loan Analytics
  27.  *  - Transaction Cost Analytics
  28.  *
  29.  *  DROP Portfolio Core implements libraries for the following:
  30.  *  - Asset Allocation Analytics
  31.  *  - Asset Liability Management Analytics
  32.  *  - Capital Estimation Analytics
  33.  *  - Exposure Analytics
  34.  *  - Margin Analytics
  35.  *  - XVA Analytics
  36.  *
  37.  *  DROP Computational Core implements libraries for the following:
  38.  *  - Algorithm Support
  39.  *  - Computation Support
  40.  *  - Function Analysis
  41.  *  - Model Validation
  42.  *  - Numerical Analysis
  43.  *  - Numerical Optimizer
  44.  *  - Spline Builder
  45.  *  - Statistical Learning
  46.  *
  47.  *  Documentation for DROP is Spread Over:
  48.  *
  49.  *  - Main                     => https://lakshmidrip.github.io/DROP/
  50.  *  - Wiki                     => https://github.com/lakshmiDRIP/DROP/wiki
  51.  *  - GitHub                   => https://github.com/lakshmiDRIP/DROP
  52.  *  - Repo Layout Taxonomy     => https://github.com/lakshmiDRIP/DROP/blob/master/Taxonomy.md
  53.  *  - Javadoc                  => https://lakshmidrip.github.io/DROP/Javadoc/index.html
  54.  *  - Technical Specifications => https://github.com/lakshmiDRIP/DROP/tree/master/Docs/Internal
  55.  *  - Release Versions         => https://lakshmidrip.github.io/DROP/version.html
  56.  *  - Community Credits        => https://lakshmidrip.github.io/DROP/credits.html
  57.  *  - Issues Catalog           => https://github.com/lakshmiDRIP/DROP/issues
  58.  *  - JUnit                    => https://lakshmidrip.github.io/DROP/junit/index.html
  59.  *  - Jacoco                   => https://lakshmidrip.github.io/DROP/jacoco/index.html
  60.  *
  61.  *  Licensed under the Apache License, Version 2.0 (the "License");
  62.  *      you may not use this file except in compliance with the License.
  63.  *  
  64.  *  You may obtain a copy of the License at
  65.  *      http://www.apache.org/licenses/LICENSE-2.0
  66.  *  
  67.  *  Unless required by applicable law or agreed to in writing, software
  68.  *      distributed under the License is distributed on an "AS IS" BASIS,
  69.  *      WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  70.  *  
  71.  *  See the License for the specific language governing permissions and
  72.  *      limitations under the License.
  73.  */

  74. /**
  75.  * <i>Kummer24</i> contains the Isomorphic Klein-4 Group of the Transformations built out of the Solutions
  76.  * emanating from the Singularities of the Hyper-geometric 2F1 Function. The References are:
  77.  *
  78.  * <br><br>
  79.  *  <ul>
  80.  *      <li>
  81.  *          Gessel, I., and D. Stanton (1982): Strange Evaluations of Hyper-geometric Series <i>SIAM Journal
  82.  *              on Mathematical Analysis</i> <b>13 (2)</b> 295-308
  83.  *      </li>
  84.  *      <li>
  85.  *          Koepf, W (1995): Algorithms for m-fold Hyper-geometric Summation <i>Journal of Symbolic
  86.  *              Computation</i> <b>20 (4)</b> 399-417
  87.  *      </li>
  88.  *      <li>
  89.  *          Lavoie, J. L., F. Grondin, and A. K. Rathie (1996): Generalization of Whipple’s Theorem on the
  90.  *              Sum of a (_2^3)F(a,b;c;z) <i>Journal of Computational and Applied Mathematics</i> <b>72</b>
  91.  *              293-300
  92.  *      </li>
  93.  *      <li>
  94.  *          National Institute of Standards and Technology (2019): Hyper-geometric Function
  95.  *              https://dlmf.nist.gov/15
  96.  *      </li>
  97.  *      <li>
  98.  *          Wikipedia (2019): Hyper-geometric Function https://en.wikipedia.org/wiki/Hypergeometric_function
  99.  *      </li>
  100.  *  </ul>
  101.  *
  102.  *  <br><br>
  103.  *  <ul>
  104.  *      <li><b>Module </b> = <a href = "https://github.com/lakshmiDRIP/DROP/tree/master/ComputationalCore.md">Computational Core Module</a></li>
  105.  *      <li><b>Library</b> = <a href = "https://github.com/lakshmiDRIP/DROP/tree/master/FunctionAnalysisLibrary.md">Function Analysis Library</a></li>
  106.  *      <li><b>Project</b> = <a href = "https://github.com/lakshmiDRIP/DROP/tree/master/src/main/java/org/drip/specialfunction/README.md">Special Function Implementation Analysis</a></li>
  107.  *      <li><b>Package</b> = <a href = "https://github.com/lakshmiDRIP/DROP/tree/master/src/main/java/org/drip/specialfunction/group/README.md">Special Function Singularity Solution Group</a></li>
  108.  *  </ul>
  109.  *
  110.  * @author Lakshmi Krishnamurthy
  111.  */

  112. public class Kummer24 extends org.drip.specialfunction.group.FuchsianEquation
  113. {

  114.     /**
  115.      * Construct the Kummer24 Isomorphic Array Version of the Fuchsian Equation
  116.      *
  117.      * @param regularHypergeometricEstimator The Regular Hyper-geometric Estimator
  118.      *
  119.      * @return The Kummer24 Isomorphic Array Version of the Fuchsian Equation
  120.      */

  121.     public static final Kummer24 Standard (
  122.         final org.drip.specialfunction.definition.RegularHypergeometricEstimator
  123.             regularHypergeometricEstimator)
  124.     {
  125.         if (null == regularHypergeometricEstimator)
  126.         {
  127.             return null;
  128.         }

  129.         org.drip.specialfunction.definition.HypergeometricParameters hypergeometricParameters =
  130.             regularHypergeometricEstimator.hypergeometricParameters();

  131.         final double a = hypergeometricParameters.a();

  132.         final double b = hypergeometricParameters.b();

  133.         final double c = hypergeometricParameters.c();

  134.         try
  135.         {
  136.             return new Kummer24 (
  137.                 new org.drip.function.definition.R1ToR1[]
  138.                 {
  139.                     regularHypergeometricEstimator.albinate (
  140.                         new org.drip.specialfunction.definition.HypergeometricParameters (
  141.                             a,
  142.                             c - b,
  143.                             c
  144.                         ),
  145.                         new org.drip.function.definition.R1ToR1 (null)
  146.                         {
  147.                             @Override public double evaluate (
  148.                                 final double z)
  149.                                 throws java.lang.Exception
  150.                             {
  151.                                 return java.lang.Math.pow (
  152.                                     1. - z,
  153.                                     -a
  154.                                 );
  155.                             }
  156.                         },
  157.                         new org.drip.function.definition.R1ToR1 (null)
  158.                         {
  159.                             @Override public double evaluate (
  160.                                 final double z)
  161.                                 throws java.lang.Exception
  162.                             {
  163.                                 return z / (z - 1.);
  164.                             }
  165.                         }
  166.                     ),
  167.                     regularHypergeometricEstimator.albinate (
  168.                         new org.drip.specialfunction.definition.HypergeometricParameters (
  169.                             a,
  170.                             b,
  171.                             1. + a + b - c
  172.                         ),
  173.                         null,
  174.                         new org.drip.function.definition.R1ToR1 (null)
  175.                         {
  176.                             @Override public double evaluate (
  177.                                 final double z)
  178.                                 throws java.lang.Exception
  179.                             {
  180.                                 return 1. - z;
  181.                             }
  182.                         }
  183.                     ),
  184.                     regularHypergeometricEstimator.albinate (
  185.                         new org.drip.specialfunction.definition.HypergeometricParameters (
  186.                             c - a,
  187.                             b,
  188.                             c
  189.                         ),
  190.                         new org.drip.function.definition.R1ToR1 (null)
  191.                         {
  192.                             @Override public double evaluate (
  193.                                 final double z)
  194.                                 throws java.lang.Exception
  195.                             {
  196.                                 return java.lang.Math.pow (
  197.                                     1. - z,
  198.                                     -b
  199.                                 );
  200.                             }
  201.                         },
  202.                         new org.drip.function.definition.R1ToR1 (null)
  203.                         {
  204.                             @Override public double evaluate (
  205.                                 final double z)
  206.                                 throws java.lang.Exception
  207.                             {
  208.                                 return z / (z - 1.);
  209.                             }
  210.                         }
  211.                     ),
  212.                 }
  213.             );
  214.         }
  215.         catch (java.lang.Exception e)
  216.         {
  217.             e.printStackTrace();
  218.         }

  219.         return null;
  220.     }

  221.     protected Kummer24 (
  222.         final org.drip.function.definition.R1ToR1[] kleinGroupFunctionArray)
  223.         throws java.lang.Exception
  224.     {
  225.         super (kleinGroupFunctionArray);
  226.     }

  227.     /**
  228.      * Generate the Transposition (12) under the Fuchsian Isomorphism with Symmetry Group on points 1, 2, 3
  229.      *
  230.      * @return The Transposition (12) under the Fuchsian Isomorphism with Symmetry Group on points 1, 2, 3
  231.      */

  232.     public org.drip.specialfunction.definition.RegularHypergeometricEstimator transposition12()
  233.     {
  234.         return (org.drip.specialfunction.definition.RegularHypergeometricEstimator)
  235.             kleinGroupFunctionArray()[0];
  236.     }

  237.     /**
  238.      * Generate the Transposition (23) under the Fuchsian Isomorphism with Symmetry Group on points 1, 2, 3
  239.      *
  240.      * @return The Transposition (23) under the Fuchsian Isomorphism with Symmetry Group on points 1, 2, 3
  241.      */

  242.     public org.drip.specialfunction.definition.RegularHypergeometricEstimator transposition23()
  243.     {
  244.         return (org.drip.specialfunction.definition.RegularHypergeometricEstimator)
  245.             kleinGroupFunctionArray()[1];
  246.     }

  247.     /**
  248.      * Generate the Transposition (34) under the Fuchsian Isomorphism with Symmetry Group on points 1, 2, 3
  249.      *
  250.      * @return The Transposition (34) under the Fuchsian Isomorphism with Symmetry Group on points 1, 2, 3
  251.      */

  252.     public org.drip.specialfunction.definition.RegularHypergeometricEstimator transposition34()
  253.     {
  254.         return (org.drip.specialfunction.definition.RegularHypergeometricEstimator)
  255.             kleinGroupFunctionArray()[2];
  256.     }
  257. }