| commit | author | age | ||
| 66d68b | 1 | /* |
| U | 2 | Zeitrechnung - a class library to determine calendar events |
| 3 | Copyright (c) 1984-2023 Ulrich Hilger, http://uhilger.de | |
| 4 | ||
| 5 | This program is free software: you can redistribute it and/or modify | |
| 6 | it under the terms of the GNU Affero General Public License as published by | |
| 7 | the Free Software Foundation, either version 3 of the License, or | |
| 8 | (at your option) any later version. | |
| 9 | ||
| 10 | This program is distributed in the hope that it will be useful, | |
| 11 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
| 12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
| 13 | GNU Affero General Public License for more details. | |
| 14 | ||
| 15 | You should have received a copy of the GNU Affero General Public License | |
| 16 | along with this program. If not, see <http://www.gnu.org/licenses/>. | |
| 17 | */ | |
| 18 | package de.uhilger.zeitrechnung.kalender; | |
| 19 | ||
| 20 | import de.uhilger.zeitrechnung.Definition; | |
| 21 | ||
| 22 | /** | |
| 23 | * Bestimmung des Ostersonntages als generisches Datum nach christlicher | |
| 24 | * sowie christlich orthodoxer Verwendung. | |
| 25 | * | |
| 26 | * @author Ulrich Hilger | |
| 27 | */ | |
| 28 | public class ChristlicherKalender extends ISOKalender { | |
| 29 | ||
| 30 | public long ostern(long gregorianischesJahr) { | |
| 31 | long jahrhundert = 1 + ganzzahlQuotient(gregorianischesJahr, 100); | |
| 32 | long veraenderlicheEpakte = modulo(14 | |
| 33 | + 11 * modulo(gregorianischesJahr, 19) | |
| 34 | - ganzzahlQuotient(3 * jahrhundert, 4) | |
| 35 | + ganzzahlQuotient(5 + 8 * jahrhundert, 25), | |
| 36 | 30); | |
| 37 | long berichtigteEpakte = veraenderlicheEpakte == 0 || | |
| 38 | (veraenderlicheEpakte == 1 && 10 < modulo(gregorianischesJahr, 19)) | |
| 39 | ? veraenderlicheEpakte + 1 | |
| 40 | : veraenderlicheEpakte; | |
| 41 | long vollmondOstern = zuTagen(gregorianischesJahr, Definition.APRIL, 19) - | |
| 42 | berichtigteEpakte; | |
| 43 | return tagNach(vollmondOstern, Definition.SONNTAG); | |
| 44 | } | |
| 45 | ||
| 46 | public long orthodoxesOstern(long gregorianischesJahr) { | |
| 47 | long vollmondOstern = 354 * gregorianischesJahr | |
| 48 | + 30 * ganzzahlQuotient((7 * gregorianischesJahr) - 8, 19) | |
| 49 | + ganzzahlQuotient(gregorianischesJahr, 4) | |
| 50 | - ganzzahlQuotient(gregorianischesJahr, 19) | |
| 51 | - 272; | |
| 52 | return tagNach(vollmondOstern, Definition.SONNTAG); | |
| 53 | } | |
| 54 | ||
| 55 | } | |
