git-svn-id: https://svn.apache.org/repos/asf/poi/trunk@1844238 13f79535-47bb-0310-9956-ffa450edef68tags/REL_4_0_1
// 247: DB | // 247: DB | ||||
// 252: FEQUENCY | // 252: FEQUENCY | ||||
retval[252] = Frequency.instance; | |||||
retval[FunctionID.EXTERNAL_FUNC] = null; // ExternalFunction is a FreeRefFunction, nominally 255 | retval[FunctionID.EXTERNAL_FUNC] = null; // ExternalFunction is a FreeRefFunction, nominally 255 | ||||
retval[261] = new Errortype(); | retval[261] = new Errortype(); |
/* ==================================================================== | |||||
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.functions; | |||||
import org.apache.poi.ss.formula.CacheAreaEval; | |||||
import org.apache.poi.ss.formula.eval.EvaluationException; | |||||
import org.apache.poi.ss.formula.eval.NumberEval; | |||||
import org.apache.poi.ss.formula.eval.ValueEval; | |||||
import java.util.Arrays; | |||||
/** | |||||
* Implementation of Excel 'Analysis ToolPak' function FREQUENCY()<br> | |||||
* Returns a frequency distribution as a vertical array<p> | |||||
* <p> | |||||
* <b>Syntax</b><br> | |||||
* <b>FREQUENCY</b>(<b>data_array</b>, <b>bins_array</b>)<p> | |||||
* <p> | |||||
* <b>data_array</b> Required. An array of or reference to a set of values for which you want to count frequencies. | |||||
* If data_array contains no values, FREQUENCY returns an array of zeros.<br> | |||||
* <b>bins_array</b> Required. An array of or reference to intervals into which you want to group the values in data_array. | |||||
* If bins_array contains no values, FREQUENCY returns the number of elements in data_array.<br> | |||||
* | |||||
* @author Yegor Kozlov | |||||
*/ | |||||
public class Frequency extends Fixed2ArgFunction { | |||||
public static final Function instance = new Frequency(); | |||||
private Frequency() { | |||||
// enforce singleton | |||||
} | |||||
public ValueEval evaluate(int srcRowIndex, int srcColumnIndex, ValueEval arg0, ValueEval arg1) { | |||||
MatrixFunction.MutableValueCollector collector = new MatrixFunction.MutableValueCollector(false, false); | |||||
double[] values; | |||||
double[] bins; | |||||
try { | |||||
values = collector.collectValues(arg0); | |||||
bins = collector.collectValues(arg1); | |||||
} catch (EvaluationException e) { | |||||
return e.getErrorEval(); | |||||
} | |||||
// can bins be not sorted? | |||||
//bins = Arrays.stream(bins).sorted().distinct().toArray(); | |||||
int[] histogram = histogram(values, bins); | |||||
NumberEval[] result = Arrays.stream(histogram).boxed().map(NumberEval::new).toArray(NumberEval[]::new); | |||||
return new CacheAreaEval(srcRowIndex, srcColumnIndex, | |||||
srcRowIndex + result.length - 1, srcColumnIndex, result); | |||||
} | |||||
static int findBin(double value, double[] bins) { | |||||
int idx = Arrays.binarySearch(bins, value); | |||||
return idx >= 0 ? idx + 1 : -idx; | |||||
} | |||||
static int[] histogram(double[] values, double[] bins) { | |||||
int[] histogram = new int[bins.length + 1]; | |||||
for (double val : values) { | |||||
histogram[findBin(val, bins) - 1]++; | |||||
} | |||||
return histogram; | |||||
} | |||||
} |
/* ==================================================================== | |||||
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.functions; | |||||
import org.apache.poi.hssf.usermodel.HSSFWorkbook; | |||||
import org.apache.poi.ss.usermodel.*; | |||||
import org.apache.poi.ss.util.CellRangeAddress; | |||||
import org.junit.Test; | |||||
import static org.apache.poi.ss.formula.functions.Frequency.histogram; | |||||
import static org.junit.Assert.assertArrayEquals; | |||||
import static org.junit.Assert.assertEquals; | |||||
/** | |||||
* Testcase for the function FREQUENCY(data, bins) | |||||
* | |||||
* @author Yegor Kozlov | |||||
*/ | |||||
public class TestFrequency { | |||||
@Test | |||||
public void testHistogram() { | |||||
assertArrayEquals(new int[]{3, 2, 2, 0, 1, 1}, | |||||
histogram( | |||||
new double[]{11, 12, 13, 21, 29, 36, 40, 58, 69}, | |||||
new double[]{20, 30, 40, 50, 60}) | |||||
); | |||||
assertArrayEquals(new int[]{1, 1, 1, 1, 1, 0}, | |||||
histogram( | |||||
new double[]{20, 30, 40, 50, 60}, | |||||
new double[]{20, 30, 40, 50, 60}) | |||||
); | |||||
assertArrayEquals(new int[]{2, 3}, | |||||
histogram( | |||||
new double[]{20, 30, 40, 50, 60}, | |||||
new double[]{30}) | |||||
); | |||||
} | |||||
@Test | |||||
public void testEvaluate() { | |||||
Workbook wb = new HSSFWorkbook(); | |||||
FormulaEvaluator evaluator = wb.getCreationHelper().createFormulaEvaluator(); | |||||
int[] data = {1, 1, 2, 3, 4, 4, 5, 7, 8, 9, 9, 11, 3, 5, 8}; | |||||
int[] bins = {3, 6, 9}; | |||||
Sheet sheet = wb.createSheet(); | |||||
Row dataRow = sheet.createRow(0); // A1:O1 | |||||
for (int i = 0; i < data.length; i++) { | |||||
dataRow.createCell(i).setCellValue(data[i]); | |||||
} | |||||
Row binsRow = sheet.createRow(1); | |||||
for (int i = 0; i < bins.length; i++) { // A2:C2 | |||||
binsRow.createCell(i).setCellValue(bins[i]); | |||||
} | |||||
Row fmlaRow = sheet.createRow(2); | |||||
CellRange<? extends Cell> arrayFmla = sheet.setArrayFormula("FREQUENCY(A1:O1,A2:C2)", CellRangeAddress.valueOf("A3:A6")); | |||||
Cell b3 = fmlaRow.createCell(1); // B3 | |||||
b3.setCellFormula("COUNT(FREQUENCY(A1:O1,A2:C2))"); // frequency returns a vertical array of bins+1 | |||||
Cell c3 = fmlaRow.createCell(2); | |||||
c3.setCellFormula("SUM(FREQUENCY(A1:O1,A2:C2))"); // sum of the frequency bins should add up to the number of data values | |||||
assertEquals(5, (int) evaluator.evaluate(arrayFmla.getFlattenedCells()[0]).getNumberValue()); | |||||
assertEquals(4, (int) evaluator.evaluate(arrayFmla.getFlattenedCells()[1]).getNumberValue()); | |||||
assertEquals(5, (int) evaluator.evaluate(arrayFmla.getFlattenedCells()[2]).getNumberValue()); | |||||
assertEquals(1, (int) evaluator.evaluate(arrayFmla.getFlattenedCells()[3]).getNumberValue()); | |||||
assertEquals(4, (int) evaluator.evaluate(b3).getNumberValue()); | |||||
assertEquals(15, (int) evaluator.evaluate(c3).getNumberValue()); | |||||
} | |||||
} |