#### /interpreter/tags/at2-build190607/src/edu/vub/at/objects/ATFraction.java

Java | 94 lines | 10 code | 12 blank | 72 comment | 0 complexity | b098b025235741d5487672c77e61acdd MD5 | raw file

1/** 2 * AmbientTalk/2 Project 3 * ATFraction.java created on 26-jul-2006 at 15:17:23 4 * (c) Programming Technology Lab, 2006 - 2007 5 * Authors: Tom Van Cutsem & Stijn Mostinckx 6 * 7 * Permission is hereby granted, free of charge, to any person 8 * obtaining a copy of this software and associated documentation 9 * files (the "Software"), to deal in the Software without 10 * restriction, including without limitation the rights to use, 11 * copy, modify, merge, publish, distribute, sublicense, and/or 12 * sell copies of the Software, and to permit persons to whom the 13 * Software is furnished to do so, subject to the following 14 * conditions: 15 * 16 * The above copyright notice and this permission notice shall be 17 * included in all copies or substantial portions of the Software. 18 * 19 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 20 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES 21 * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 22 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT 23 * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, 24 * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING 25 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR 26 * OTHER DEALINGS IN THE SOFTWARE. 27 */ 28package edu.vub.at.objects; 29 30import edu.vub.at.exceptions.InterpreterException; 31 32 33/** 34 * ATFraction is the public interface to a native AmbientTalk fraction (a floating point value). 35 * 36 * @author tvc 37 */ 38public interface ATFraction extends ATNumeric { 39 40 41 //arithmetic operations 42 /** 43 * Returns the fraction plus 1. 44 * 45 * @return an ATFraction resulting of adding 1 to the receiver. 46 */ 47 public ATFraction base_inc() throws InterpreterException; 48 49 /** 50 * Returns the fraction minus 1. 51 * 52 * @return an ATFraction resulting of subtracting 1 to the receiver. 53 */ 54 public ATFraction base_dec() throws InterpreterException; 55 56 /** 57 * Returns the absolute value of a fraction. 58 * <p> 59 * More specifically: 60 * <ul> 61 * <li>If the receiver >= 0, the receiver is returned. 62 * <li>If the receiver < 0, the negation of the receiver is returned. 63 * </ul> 64 * 65 * @return the absolute value of the receiver. 66 */ 67 public ATFraction base_abs() throws InterpreterException; 68 69 // base-level interface 70 71 /** 72 * Returns the closest number to the fraction. 73 * <p> 74 * More specifically, rounding a number is equivalent to <code> (fraction + 0.5).floor() </code> 75 * 76 * @return an ATNumber resulting of rounding the receiver to the closest number value. 77 */ 78 public ATNumber base_round() throws InterpreterException; 79 80 /** 81 * Returns the closest number to positive infinity that is smaller than the fraction. 82 * 83 * @return the closest number to positive infinity that is smaller than the fraction. 84 */ 85 public ATNumber base_floor() throws InterpreterException; 86 87 /** 88 * Returns the closest number to negative infinity that is greater than the fraction. 89 * 90 * @return the closest number to negative infinity that is greater than the fraction. 91 */ 92 public ATNumber base_ceiling() throws InterpreterException; 93 94}