| 1 | /* | 
| 2 | * Copyright (c) 2005 The University of Notre Dame. All Rights Reserved. | 
| 3 | * | 
| 4 | * The University of Notre Dame grants you ("Licensee") a | 
| 5 | * non-exclusive, royalty free, license to use, modify and | 
| 6 | * redistribute this software in source and binary code form, provided | 
| 7 | * that the following conditions are met: | 
| 8 | * | 
| 9 | * 1. Acknowledgement of the program authors must be made in any | 
| 10 | *    publication of scientific results based in part on use of the | 
| 11 | *    program.  An acceptable form of acknowledgement is citation of | 
| 12 | *    the article in which the program was described (Matthew | 
| 13 | *    A. Meineke, Charles F. Vardeman II, Teng Lin, Christopher | 
| 14 | *    J. Fennell and J. Daniel Gezelter, "OOPSE: An Object-Oriented | 
| 15 | *    Parallel Simulation Engine for Molecular Dynamics," | 
| 16 | *    J. Comput. Chem. 26, pp. 252-271 (2005)) | 
| 17 | * | 
| 18 | * 2. Redistributions of source code must retain the above copyright | 
| 19 | *    notice, this list of conditions and the following disclaimer. | 
| 20 | * | 
| 21 | * 3. Redistributions in binary form must reproduce the above copyright | 
| 22 | *    notice, this list of conditions and the following disclaimer in the | 
| 23 | *    documentation and/or other materials provided with the | 
| 24 | *    distribution. | 
| 25 | * | 
| 26 | * This software is provided "AS IS," without a warranty of any | 
| 27 | * kind. All express or implied conditions, representations and | 
| 28 | * warranties, including any implied warranty of merchantability, | 
| 29 | * fitness for a particular purpose or non-infringement, are hereby | 
| 30 | * excluded.  The University of Notre Dame and its licensors shall not | 
| 31 | * be liable for any damages suffered by licensee as a result of | 
| 32 | * using, modifying or distributing the software or its | 
| 33 | * derivatives. In no event will the University of Notre Dame or its | 
| 34 | * licensors be liable for any lost revenue, profit or data, or for | 
| 35 | * direct, indirect, special, consequential, incidental or punitive | 
| 36 | * damages, however caused and regardless of the theory of liability, | 
| 37 | * arising out of the use of or inability to use software, even if the | 
| 38 | * University of Notre Dame has been advised of the possibility of | 
| 39 | * such damages. | 
| 40 | */ | 
| 41 |  | 
| 42 | #include "math/LegendrePolynomial.hpp" | 
| 43 |  | 
| 44 | namespace oopse { | 
| 45 | LegendrePolynomial::LegendrePolynomial(int maxPower) : maxPower_(maxPower){ | 
| 46 |  | 
| 47 | assert(maxPower >= 0); | 
| 48 | GeneratePolynomials(maxPower_); | 
| 49 | } | 
| 50 |  | 
| 51 | void LegendrePolynomial::GeneratePolynomials(int maxPower) { | 
| 52 |  | 
| 53 | GenerateFirstTwoTerms(); | 
| 54 |  | 
| 55 | DoublePolynomial x; | 
| 56 | x.setCoefficient(1, 1.0); | 
| 57 |  | 
| 58 | //recursive generate the high order term of Legendre Polynomials | 
| 59 | //P_{l+1}= \frac{(2l+1)(x)P_l-l P_{l-1}{l+1} | 
| 60 | for (int i = 2; i <= maxPower; ++i) { | 
| 61 | DoublePolynomial pn; | 
| 62 | RealType tmp1 = (2.0*i-1.0)/i; | 
| 63 | RealType tmp2 = (i-1.0)/i; | 
| 64 | pn = polyList_[i-1] * x * tmp1 - polyList_[i-2] * tmp2; | 
| 65 | polyList_.push_back(pn); | 
| 66 | } | 
| 67 | } | 
| 68 |  | 
| 69 |  | 
| 70 | void LegendrePolynomial::GenerateFirstTwoTerms() { | 
| 71 | DoublePolynomial p0; | 
| 72 | p0.setCoefficient(0, 1.0); | 
| 73 | polyList_.push_back(p0); | 
| 74 |  | 
| 75 | DoublePolynomial p1; | 
| 76 | p1.setCoefficient(1, 1.0); | 
| 77 | polyList_.push_back(p1); | 
| 78 | } | 
| 79 |  | 
| 80 | } |