| /* ==================================================================== |
| Licensed to the Apache Software Foundation (ASF) under one or more |
| contributor license agreements. See the NOTICE file distributed with |
| this work for additional information regarding copyright ownership. |
| The ASF licenses this file to You under the Apache License, Version 2.0 |
| (the "License"); you may not use this file except in compliance with |
| the License. You may obtain a copy of the License at |
| |
| http://www.apache.org/licenses/LICENSE-2.0 |
| |
| Unless required by applicable law or agreed to in writing, software |
| distributed under the License is distributed on an "AS IS" BASIS, |
| WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| See the License for the specific language governing permissions and |
| limitations under the License. |
| ==================================================================== */ |
| package org.apache.poi.ss.formula.atp; |
| |
| import org.apache.poi.ss.formula.eval.ErrorEval; |
| import org.apache.poi.ss.formula.eval.EvaluationException; |
| import org.apache.poi.ss.formula.eval.NumberEval; |
| import org.apache.poi.ss.formula.eval.OperandResolver; |
| import org.apache.poi.ss.formula.eval.ValueEval; |
| import org.apache.poi.ss.formula.functions.FreeRefFunction; |
| import org.apache.poi.ss.formula.OperationEvaluationContext; |
| |
| /** |
| * Implementation of Excel 'Analysis ToolPak' function RANDBETWEEN()<br/> |
| * |
| * Returns a random integer number between the numbers you specify.<p/> |
| * |
| * <b>Syntax</b><br/> |
| * <b>RANDBETWEEN</b>(<b>bottom</b>, <b>top</b>)<p/> |
| * |
| * <b>bottom</b> is the smallest integer RANDBETWEEN will return.<br/> |
| * <b>top</b> is the largest integer RANDBETWEEN will return.<br/> |
| |
| * @author Brendan Nolan |
| */ |
| final class RandBetween implements FreeRefFunction{ |
| |
| public static final FreeRefFunction instance = new RandBetween(); |
| |
| private RandBetween() { |
| //enforces singleton |
| } |
| |
| /** |
| * Evaluate for RANDBETWEEN(). Must be given two arguments. Bottom must be greater than top. |
| * Bottom is rounded up and top value is rounded down. After rounding top has to be set greater |
| * than top. |
| * |
| * @see org.apache.poi.ss.formula.functions.FreeRefFunction#evaluate(org.apache.poi.ss.formula.eval.ValueEval[], org.apache.poi.ss.formula.OperationEvaluationContext) |
| */ |
| public ValueEval evaluate(ValueEval[] args, OperationEvaluationContext ec) { |
| |
| double bottom, top; |
| |
| if (args.length != 2) { |
| return ErrorEval.VALUE_INVALID; |
| } |
| |
| try { |
| bottom = OperandResolver.coerceValueToDouble(OperandResolver.getSingleValue(args[0], ec.getRowIndex(), ec.getColumnIndex())); |
| top = OperandResolver.coerceValueToDouble(OperandResolver.getSingleValue(args[1], ec.getRowIndex(), ec.getColumnIndex())); |
| if(bottom > top) { |
| return ErrorEval.NUM_ERROR; |
| } |
| } catch (EvaluationException e) { |
| return ErrorEval.VALUE_INVALID; |
| } |
| |
| bottom = Math.ceil(bottom); |
| top = Math.floor(top); |
| |
| if(bottom > top) { |
| top = bottom; |
| } |
| |
| return new NumberEval((bottom + (int)(Math.random() * ((top - bottom) + 1)))); |
| |
| } |
| |
| } |