QGIS API Documentation 3.99.0-Master (09f76ad7019)
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qgsalgorithmbasicstatistics.cpp
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1/***************************************************************************
2 qgsalgorithmbasicstatistics.cpp
3 ------------------------------
4 begin : June 2024
5 copyright : (C) 2024 by Alexander Bruy
6 email : alexander dot bruy at gmail dot com
7 ***************************************************************************/
8
9/***************************************************************************
10 * *
11 * This program is free software; you can redistribute it and/or modify *
12 * it under the terms of the GNU General Public License as published by *
13 * the Free Software Foundation; either version 2 of the License, or *
14 * (at your option) any later version. *
15 * *
16 ***************************************************************************/
17
18#include "qgsalgorithmbasicstatistics.h"
19
20#include "qgsdatetimestatisticalsummary.h"
21#include "qgsstatisticalsummary.h"
22#include "qgsstringstatisticalsummary.h"
23
24#include <QString>
25
26using namespace Qt::StringLiterals;
27
29
30QString QgsBasicStatisticsAlgorithm::name() const
31{
32 return u"basicstatisticsforfields"_s;
33}
34
35QString QgsBasicStatisticsAlgorithm::displayName() const
36{
37 return QObject::tr( "Basic statistics for fields" );
38}
39
40QStringList QgsBasicStatisticsAlgorithm::tags() const
41{
42 return QObject::tr( "stats,statistics,date,time,datetime,string,number,text,table,layer,sum,maximum,minimum,mean,average,standard,deviation,count,distinct,unique,variance,median,quartile,range,majority,minority,summary" ).split( ',' );
43}
44
45QString QgsBasicStatisticsAlgorithm::group() const
46{
47 return QObject::tr( "Vector analysis" );
48}
49
50QString QgsBasicStatisticsAlgorithm::groupId() const
51{
52 return u"vectoranalysis"_s;
53}
54
55QString QgsBasicStatisticsAlgorithm::shortHelpString() const
56{
57 return QObject::tr( "This algorithm generates basic statistics from the analysis of values in a field in the attribute table of a vector layer. Numeric, date, time and string fields are supported. The statistics returned will depend on the field type." );
58}
59
60QString QgsBasicStatisticsAlgorithm::shortDescription() const
61{
62 return QObject::tr( "Generates basic statistics from the values in a field of a vector layer." );
63}
64
65QgsBasicStatisticsAlgorithm *QgsBasicStatisticsAlgorithm::createInstance() const
66{
67 return new QgsBasicStatisticsAlgorithm();
68}
69
70void QgsBasicStatisticsAlgorithm::initAlgorithm( const QVariantMap & )
71{
72 addParameter( new QgsProcessingParameterFeatureSource( u"INPUT_LAYER"_s, QObject::tr( "Input layer" ), QList<int>() << static_cast<int>( Qgis::ProcessingSourceType::Vector ) ) );
73 addParameter( new QgsProcessingParameterField( u"FIELD_NAME"_s, QObject::tr( "Field to calculate statistics on" ), QVariant(), u"INPUT_LAYER"_s ) );
74 addParameter( new QgsProcessingParameterFeatureSink( u"OUTPUT"_s, QObject::tr( "Statistics" ), Qgis::ProcessingSourceType::Vector, QVariant(), true ) );
75 addParameter( new QgsProcessingParameterFileDestination( u"OUTPUT_HTML_FILE"_s, QObject::tr( "Statistics report" ), QObject::tr( "'HTML files (*.html)" ), QVariant(), true ) );
76
77 addOutput( new QgsProcessingOutputNumber( u"COUNT"_s, QObject::tr( "Count" ) ) );
78 addOutput( new QgsProcessingOutputNumber( u"UNIQUE"_s, QObject::tr( "Number of unique values" ) ) );
79 addOutput( new QgsProcessingOutputNumber( u"EMPTY"_s, QObject::tr( "Number of empty (null) values" ) ) );
80 addOutput( new QgsProcessingOutputNumber( u"FILLED"_s, QObject::tr( "Number of non-empty values" ) ) );
81 addOutput( new QgsProcessingOutputNumber( u"MIN"_s, QObject::tr( "Minimum value" ) ) );
82 addOutput( new QgsProcessingOutputNumber( u"MAX"_s, QObject::tr( "Maximum value" ) ) );
83 addOutput( new QgsProcessingOutputNumber( u"MIN_LENGTH"_s, QObject::tr( "Minimum length" ) ) );
84 addOutput( new QgsProcessingOutputNumber( u"MAX_LENGTH"_s, QObject::tr( "Maximum length" ) ) );
85 addOutput( new QgsProcessingOutputNumber( u"MEAN_LENGTH"_s, QObject::tr( "Mean length" ) ) );
86 addOutput( new QgsProcessingOutputNumber( u"CV"_s, QObject::tr( "Coefficient of Variation" ) ) );
87 addOutput( new QgsProcessingOutputNumber( u"SUM"_s, QObject::tr( "Sum" ) ) );
88 addOutput( new QgsProcessingOutputNumber( u"MEAN"_s, QObject::tr( "Mean value" ) ) );
89 addOutput( new QgsProcessingOutputNumber( u"STD_DEV"_s, QObject::tr( "Standard deviation" ) ) );
90 addOutput( new QgsProcessingOutputNumber( u"RANGE"_s, QObject::tr( "Range" ) ) );
91 addOutput( new QgsProcessingOutputNumber( u"MEDIAN"_s, QObject::tr( "Median" ) ) );
92 addOutput( new QgsProcessingOutputNumber( u"MINORITY"_s, QObject::tr( "Minority (rarest occurring value)" ) ) );
93 addOutput( new QgsProcessingOutputNumber( u"MAJORITY"_s, QObject::tr( "Majority (most frequently occurring value)" ) ) );
94 addOutput( new QgsProcessingOutputNumber( u"FIRSTQUARTILE"_s, QObject::tr( "First quartile" ) ) );
95 addOutput( new QgsProcessingOutputNumber( u"THIRDQUARTILE"_s, QObject::tr( "Third quartile" ) ) );
96 addOutput( new QgsProcessingOutputNumber( u"IQR"_s, QObject::tr( "Interquartile Range (IQR)" ) ) );
97}
98
99QVariantMap QgsBasicStatisticsAlgorithm::processAlgorithm( const QVariantMap &parameters, QgsProcessingContext &context, QgsProcessingFeedback *feedback )
100{
101 std::unique_ptr<QgsProcessingFeatureSource> source( parameterAsSource( parameters, u"INPUT_LAYER"_s, context ) );
102 if ( !source )
103 throw QgsProcessingException( invalidSourceError( parameters, u"INPUT_LAYER"_s ) );
104
105 const QString fieldName = parameterAsString( parameters, u"FIELD_NAME"_s, context );
106 const int fieldIndex = source->fields().lookupField( fieldName );
107 if ( fieldIndex < 0 )
108 {
109 throw QgsProcessingException( QObject::tr( "Invalid field for statistics: “%1” does not exist" ).arg( fieldName ) );
110 }
111
112 QgsField field = source->fields().at( fieldIndex );
113
114 QString outputHtml = parameterAsFileOutput( parameters, u"OUTPUT_HTML_FILE"_s, context );
115
116 QgsFeatureRequest request;
117 request.setFlags( Qgis::FeatureRequestFlag::NoGeometry ).setSubsetOfAttributes( QStringList() << fieldName, source->fields() );
118 QgsFeatureIterator features = source->getFeatures( request, Qgis::ProcessingFeatureSourceFlag::SkipGeometryValidityChecks );
119 const long long count = source->featureCount();
120
121 QgsFields fields;
122 fields.append( QgsField( u"count"_s, QMetaType::Int ) );
123 fields.append( QgsField( u"unique"_s, QMetaType::Int ) );
124 fields.append( QgsField( u"empty"_s, QMetaType::Int ) );
125 fields.append( QgsField( u"filled"_s, QMetaType::Int ) );
126
127 if ( field.isNumeric() )
128 {
129 fields.append( QgsField( u"min"_s, QMetaType::Double ) );
130 fields.append( QgsField( u"max"_s, QMetaType::Double ) );
131 fields.append( QgsField( u"range"_s, QMetaType::Double ) );
132 fields.append( QgsField( u"sum"_s, QMetaType::Double ) );
133 fields.append( QgsField( u"mean"_s, QMetaType::Double ) );
134 fields.append( QgsField( u"median"_s, QMetaType::Double ) );
135 fields.append( QgsField( u"stddev"_s, QMetaType::Double ) );
136 fields.append( QgsField( u"cv"_s, QMetaType::Double ) );
137 fields.append( QgsField( u"minority"_s, QMetaType::Double ) );
138 fields.append( QgsField( u"majority"_s, QMetaType::Double ) );
139 fields.append( QgsField( u"q1"_s, QMetaType::Double ) );
140 fields.append( QgsField( u"q3"_s, QMetaType::Double ) );
141 fields.append( QgsField( u"iqr"_s, QMetaType::Double ) );
142 }
143 else if ( field.isDateOrTime() )
144 {
145 if ( field.type() == QMetaType::Type::QDate )
146 {
147 fields.append( QgsField( u"min"_s, QMetaType::QDate ) );
148 fields.append( QgsField( u"max"_s, QMetaType::QDate ) );
149 }
150 else if ( field.type() == QMetaType::Type::QTime )
151 {
152 fields.append( QgsField( u"min"_s, QMetaType::QTime ) );
153 fields.append( QgsField( u"max"_s, QMetaType::QTime ) );
154 }
155 else
156 {
157 fields.append( QgsField( u"min"_s, QMetaType::QDateTime ) );
158 fields.append( QgsField( u"max"_s, QMetaType::QDateTime ) );
159 }
160 fields.append( QgsField( u"range"_s, QMetaType::Double ) );
161 }
162 else
163 {
164 fields.append( QgsField( u"min"_s, QMetaType::QString ) );
165 fields.append( QgsField( u"max"_s, QMetaType::QString ) );
166 fields.append( QgsField( u"min_length"_s, QMetaType::Double ) );
167 fields.append( QgsField( u"max_length"_s, QMetaType::Double ) );
168 fields.append( QgsField( u"mean_length"_s, QMetaType::Double ) );
169 fields.append( QgsField( u"minority"_s, QMetaType::QString ) );
170 fields.append( QgsField( u"majority"_s, QMetaType::QString ) );
171 }
172
173 QString destId;
174 std::unique_ptr<QgsFeatureSink> sink( parameterAsSink( parameters, u"OUTPUT"_s, context, destId, fields, Qgis::WkbType::NoGeometry, QgsCoordinateReferenceSystem() ) );
175 if ( parameters.value( u"OUTPUT"_s ).isValid() && !sink )
176 throw QgsProcessingException( invalidSinkError( parameters, u"OUTPUT"_s ) );
177
178 QStringList data;
179 data << QObject::tr( "Analyzed field: %1" ).arg( fieldName );
180
181 QVariantMap outputs;
182
183 if ( field.isNumeric() )
184 {
185 outputs = calculateNumericStatistics( parameters, fieldIndex, features, count, sink.get(), data, feedback );
186 }
187 else if ( field.isDateOrTime() )
188 {
189 outputs = calculateDateTimeStatistics( parameters, fieldIndex, field, features, count, sink.get(), data, feedback );
190 }
191 else
192 {
193 outputs = calculateStringStatistics( parameters, fieldIndex, features, count, sink.get(), data, feedback );
194 }
195 if ( sink )
196 sink->finalize();
197
198 if ( !outputHtml.isEmpty() )
199 {
200 QFile file( outputHtml );
201 if ( file.open( QIODevice::WriteOnly | QIODevice::Truncate ) )
202 {
203 QTextStream out( &file );
204 out << u"<html><head><meta http-equiv=\"Content-Type\" content=\"text/html;charset=utf-8\"/></head><body>\n"_s;
205 for ( const QString &s : data )
206 {
207 out << u"<p>%1</p>"_s.arg( s );
208 }
209 out << u"</body></html>"_s;
210
211 outputs.insert( u"OUTPUT_HTML_FILE"_s, outputHtml );
212 }
213 }
214
215 if ( sink )
216 {
217 outputs.insert( u"OUTPUT"_s, destId );
218 }
219
220 return outputs;
221}
222
223QVariantMap QgsBasicStatisticsAlgorithm::calculateNumericStatistics( const QVariantMap &parameters, const int fieldIndex, QgsFeatureIterator features, const long long count, QgsFeatureSink *sink, QStringList &data, QgsProcessingFeedback *feedback )
224{
225 const double step = count > 0 ? 100.0 / count : 1;
226 long long current = 0;
227
228 QgsFeature f;
229 QgsStatisticalSummary stat;
230
231 while ( features.nextFeature( f ) )
232 {
233 if ( feedback->isCanceled() )
234 {
235 break;
236 }
237
238 stat.addVariant( f.attribute( fieldIndex ) );
239 feedback->setProgress( current * step );
240 current++;
241 }
242 stat.finalize();
243
244 const double cv = stat.mean() != 0 ? stat.stDev() / stat.mean() : 0;
245
246 QVariantMap outputs;
247 outputs.insert( u"COUNT"_s, stat.count() );
248 outputs.insert( u"UNIQUE"_s, stat.variety() );
249 outputs.insert( u"EMPTY"_s, stat.countMissing() );
250 outputs.insert( u"FILLED"_s, count - stat.countMissing() );
251 outputs.insert( u"MIN"_s, stat.min() );
252 outputs.insert( u"MAX"_s, stat.max() );
253 outputs.insert( u"RANGE"_s, stat.range() );
254 outputs.insert( u"SUM"_s, stat.sum() );
255 outputs.insert( u"MEAN"_s, stat.mean() );
256 outputs.insert( u"MEDIAN"_s, stat.median() );
257 outputs.insert( u"STD_DEV"_s, stat.stDev() );
258 outputs.insert( u"CV"_s, cv );
259 outputs.insert( u"MINORITY"_s, stat.minority() );
260 outputs.insert( u"MAJORITY"_s, stat.majority() );
261 outputs.insert( u"FIRSTQUARTILE"_s, stat.firstQuartile() );
262 outputs.insert( u"THIRDQUARTILE"_s, stat.thirdQuartile() );
263 outputs.insert( u"IQR"_s, stat.interQuartileRange() );
264
265 data << QObject::tr( "Count: %1" ).arg( stat.count() )
266 << QObject::tr( "Unique values: %1" ).arg( stat.variety() )
267 << QObject::tr( "NULL (missing) values: %1" ).arg( stat.countMissing() )
268 << QObject::tr( "NOT NULL (filled) values: %1" ).arg( count - stat.countMissing() )
269 << QObject::tr( "Minimum value: %1" ).arg( stat.min() )
270 << QObject::tr( "Maximum value: %1" ).arg( stat.max() )
271 << QObject::tr( "Range: %1" ).arg( stat.range() )
272 << QObject::tr( "Sum: %1" ).arg( stat.sum(), 0, 'f' )
273 << QObject::tr( "Mean value: %1" ).arg( stat.mean(), 0, 'f' )
274 << QObject::tr( "Median value: %1" ).arg( stat.median(), 0, 'f' )
275 << QObject::tr( "Standard deviation: %1" ).arg( stat.stDev(), 0, 'f', 12 )
276 << QObject::tr( "Coefficient of Variation: %1" ).arg( cv, 0, 'f' )
277 << QObject::tr( "Minority (rarest occurring value): %1" ).arg( stat.minority() )
278 << QObject::tr( "Majority (most frequently occurring value): %1" ).arg( stat.majority() )
279 << QObject::tr( "First quartile: %1" ).arg( stat.firstQuartile(), 0, 'f' )
280 << QObject::tr( "Third quartile: %1" ).arg( stat.thirdQuartile(), 0, 'f' )
281 << QObject::tr( "Interquartile Range (IQR): %1" ).arg( stat.interQuartileRange() );
282
283 if ( sink )
284 {
285 QgsFeature f;
286 f.setAttributes( QgsAttributes() << outputs.value( u"COUNT"_s ) << outputs.value( u"UNIQUE"_s ) << outputs.value( u"EMPTY"_s ) << outputs.value( u"FILLED"_s ) << outputs.value( u"MIN"_s ) << outputs.value( u"MAX"_s ) << outputs.value( u"RANGE"_s ) << outputs.value( u"SUM"_s ) << outputs.value( u"MEAN"_s ) << outputs.value( u"MEDIAN"_s ) << outputs.value( u"STD_DEV"_s ) << outputs.value( u"CV"_s ) << outputs.value( u"MINORITY"_s ) << outputs.value( u"MAJORITY"_s ) << outputs.value( u"FIRSTQUARTILE"_s ) << outputs.value( u"THIRDQUARTILE"_s ) << outputs.value( u"IQR"_s ) );
287 if ( !sink->addFeature( f, QgsFeatureSink::FastInsert ) )
288 {
289 throw QgsProcessingException( writeFeatureError( sink, parameters, QString() ) );
290 }
291 }
292
293 return outputs;
294}
295
296QVariantMap QgsBasicStatisticsAlgorithm::calculateDateTimeStatistics( const QVariantMap &parameters, const int fieldIndex, QgsField field, QgsFeatureIterator features, const long long count, QgsFeatureSink *sink, QStringList &data, QgsProcessingFeedback *feedback )
297{
298 const double step = count > 0 ? 100.0 / count : 1;
299 long long current = 0;
300
301 QgsFeature f;
302 QgsDateTimeStatisticalSummary stat;
303
304 while ( features.nextFeature( f ) )
305 {
306 if ( feedback->isCanceled() )
307 {
308 break;
309 }
310
311 stat.addValue( f.attribute( fieldIndex ) );
312 feedback->setProgress( current * step );
313 current++;
314 }
315 stat.finalize();
316
317 QVariantMap outputs;
318 outputs.insert( u"COUNT"_s, stat.count() );
319 outputs.insert( u"UNIQUE"_s, stat.countDistinct() );
320 outputs.insert( u"EMPTY"_s, stat.countMissing() );
321 outputs.insert( u"FILLED"_s, stat.count() - stat.countMissing() );
322 outputs.insert( u"MIN"_s, stat.statistic( Qgis::DateTimeStatistic::Min ) );
323 outputs.insert( u"MAX"_s, stat.statistic( Qgis::DateTimeStatistic::Max ) );
324 outputs.insert( u"RANGE"_s, stat.range().seconds() );
325
326 data << QObject::tr( "Count: %1" ).arg( stat.count() )
327 << QObject::tr( "Unique values: %1" ).arg( stat.countDistinct() )
328 << QObject::tr( "NULL (missing) values: %1" ).arg( stat.countMissing() )
329 << QObject::tr( "NOT NULL (filled) values: %1" ).arg( stat.count() - stat.countMissing() )
330 << QObject::tr( "Minimum value: %1" ).arg( field.displayString( stat.statistic( Qgis::DateTimeStatistic::Min ) ) )
331 << QObject::tr( "Maximum value: %1" ).arg( field.displayString( stat.statistic( Qgis::DateTimeStatistic::Max ) ) )
332 << QObject::tr( "Range (seconds): %1" ).arg( stat.range().seconds() );
333
334 if ( sink )
335 {
336 QgsFeature f;
337 f.setAttributes( QgsAttributes() << outputs.value( u"COUNT"_s ) << outputs.value( u"UNIQUE"_s ) << outputs.value( u"EMPTY"_s ) << outputs.value( u"FILLED"_s ) << outputs.value( u"MIN"_s ) << outputs.value( u"MAX"_s ) << outputs.value( u"RANGE"_s ) );
338 if ( !sink->addFeature( f, QgsFeatureSink::FastInsert ) )
339 {
340 throw QgsProcessingException( writeFeatureError( sink, parameters, QString() ) );
341 }
342 }
343
344 return outputs;
345}
346
347QVariantMap QgsBasicStatisticsAlgorithm::calculateStringStatistics( const QVariantMap &parameters, const int fieldIndex, QgsFeatureIterator features, const long long count, QgsFeatureSink *sink, QStringList &data, QgsProcessingFeedback *feedback )
348{
349 const double step = count > 0 ? 100.0 / count : 1;
350 long long current = 0;
351
352 QgsFeature f;
353 QgsStringStatisticalSummary stat;
354
355 while ( features.nextFeature( f ) )
356 {
357 if ( feedback->isCanceled() )
358 {
359 break;
360 }
361
362 stat.addValue( f.attribute( fieldIndex ) );
363 feedback->setProgress( current * step );
364 current++;
365 }
366 stat.finalize();
367
368 QVariantMap outputs;
369 outputs.insert( u"COUNT"_s, stat.count() );
370 outputs.insert( u"UNIQUE"_s, stat.countDistinct() );
371 outputs.insert( u"EMPTY"_s, stat.countMissing() );
372 outputs.insert( u"FILLED"_s, stat.count() - stat.countMissing() );
373 outputs.insert( u"MIN"_s, stat.min() );
374 outputs.insert( u"MAX"_s, stat.max() );
375 outputs.insert( u"MIN_LENGTH"_s, stat.minLength() );
376 outputs.insert( u"MAX_LENGTH"_s, stat.maxLength() );
377 outputs.insert( u"MEAN_LENGTH"_s, stat.meanLength() );
378 outputs.insert( u"MINORITY"_s, stat.minority() );
379 outputs.insert( u"MAJORITY"_s, stat.majority() );
380
381 data << QObject::tr( "Count: %1" ).arg( stat.count() )
382 << QObject::tr( "Unique values: %1" ).arg( stat.countDistinct() )
383 << QObject::tr( "NULL (missing) values: %1" ).arg( stat.countMissing() )
384 << QObject::tr( "NOT NULL (filled) values: %1" ).arg( count - stat.countMissing() )
385 << QObject::tr( "Minimum value: %1" ).arg( stat.min() )
386 << QObject::tr( "Maximum value: %1" ).arg( stat.max() )
387 << QObject::tr( "Minimum length: %1" ).arg( stat.minLength() )
388 << QObject::tr( "Maximum length: %1" ).arg( stat.maxLength() )
389 << QObject::tr( "Mean length: %1" ).arg( stat.meanLength(), 0, 'f' )
390 << QObject::tr( "Minority: %1" ).arg( stat.minority() )
391 << QObject::tr( "Majority: %1" ).arg( stat.majority() );
392
393 if ( sink )
394 {
395 QgsFeature f;
396 f.setAttributes( QgsAttributes() << outputs.value( u"COUNT"_s ) << outputs.value( u"UNIQUE"_s ) << outputs.value( u"EMPTY"_s ) << outputs.value( u"FILLED"_s ) << outputs.value( u"MIN"_s ) << outputs.value( u"MAX"_s ) << outputs.value( u"MIN_LENGTH"_s ) << outputs.value( u"MAX_LENGTH"_s ) << outputs.value( u"MEAN_LENGTH"_s ) << outputs.value( u"MINORITY"_s ) << outputs.value( u"MAJORITY"_s ) );
397 if ( !sink->addFeature( f, QgsFeatureSink::FastInsert ) )
398 {
399 throw QgsProcessingException( writeFeatureError( sink, parameters, QString() ) );
400 }
401 }
402
403 return outputs;
404}
405
Qgis::ProcessingSourceType::Vector
@ Vector
Tables (i.e. vector layers with or without geometry). When used for a sink this indicates the sink ha...
Definition qgis.h:3610
Qgis::FeatureRequestFlag::NoGeometry
@ NoGeometry
Geometry is not required. It may still be returned if e.g. required for a filter condition.
Definition qgis.h:2254
Qgis::ProcessingFeatureSourceFlag::SkipGeometryValidityChecks
@ SkipGeometryValidityChecks
Invalid geometry checks should always be skipped. This flag can be useful for algorithms which always...
Definition qgis.h:3782
Qgis::WkbType::NoGeometry
@ NoGeometry
No geometry.
Definition qgis.h:298
Qgis::DateTimeStatistic::Max
@ Max
Maximum (latest) datetime value.
Definition qgis.h:6191
Qgis::DateTimeStatistic::Min
@ Min
Minimum (earliest) datetime value.
Definition qgis.h:6190
QgsAttributes
A vector of attributes.
Definition qgsattributes.h:57
QgsCoordinateReferenceSystem
Represents a coordinate reference system (CRS).
Definition qgscoordinatereferencesystem.h:216
QgsDateTimeStatisticalSummary
Calculator for summary statistics and aggregates for a list of datetimes.
Definition qgsdatetimestatisticalsummary.h:46
QgsDateTimeStatisticalSummary::statistic
QVariant statistic(Qgis::DateTimeStatistic stat) const
Returns the value of a specified statistic.
Definition qgsdatetimestatisticalsummary.cpp:133
QgsDateTimeStatisticalSummary::range
QgsInterval range() const
Returns the range (interval between earliest and latest non-null datetime values).
Definition qgsdatetimestatisticalsummary.cpp:159
QgsDateTimeStatisticalSummary::addValue
void addValue(const QVariant &value)
Adds a single datetime to the statistics calculation.
Definition qgsdatetimestatisticalsummary.cpp:63
QgsDateTimeStatisticalSummary::finalize
void finalize()
Must be called after adding all datetimes with addValue() and before retrieving any calculated dateti...
Definition qgsdatetimestatisticalsummary.cpp:92
QgsDateTimeStatisticalSummary::count
int count() const
Returns the calculated count of values.
Definition qgsdatetimestatisticalsummary.h:115
QgsDateTimeStatisticalSummary::countMissing
int countMissing() const
Returns the number of missing (null) datetime values.
Definition qgsdatetimestatisticalsummary.h:130
QgsDateTimeStatisticalSummary::countDistinct
int countDistinct() const
Returns the number of distinct datetime values.
Definition qgsdatetimestatisticalsummary.h:120
QgsFeatureIterator
Wrapper for iterator of features from vector data provider or vector layer.
Definition qgsfeatureiterator.h:290
QgsFeatureIterator::nextFeature
bool nextFeature(QgsFeature &f)
Fetch next feature and stores in f, returns true on success.
Definition qgsfeatureiterator.h:407
QgsFeatureRequest
Wraps a request for features to a vector layer (or directly its vector data provider).
Definition qgsfeaturerequest.h:85
QgsFeatureRequest::setFlags
QgsFeatureRequest & setFlags(Qgis::FeatureRequestFlags flags)
Sets flags that affect how features will be fetched.
Definition qgsfeaturerequest.cpp:348
QgsFeatureRequest::setSubsetOfAttributes
QgsFeatureRequest & setSubsetOfAttributes(const QgsAttributeList &attrs)
Set a subset of attributes that will be fetched.
Definition qgsfeaturerequest.cpp:354
QgsFeatureSink
An interface for objects which accept features via addFeature(s) methods.
Definition qgsfeaturesink.h:33
QgsFeatureSink::addFeature
virtual bool addFeature(QgsFeature &feature, QgsFeatureSink::Flags flags=QgsFeatureSink::Flags())
Adds a single feature to the sink.
Definition qgsfeaturesink.cpp:25
QgsFeatureSink::FastInsert
@ FastInsert
Use faster inserts, at the cost of updating the passed features to reflect changes made at the provid...
Definition qgsfeaturesink.h:69
QgsFeature
The feature class encapsulates a single feature including its unique ID, geometry and a list of field...
Definition qgsfeature.h:60
QgsFeature::setAttributes
void setAttributes(const QgsAttributes &attrs)
Sets the feature's attributes.
Definition qgsfeature.cpp:169
QgsFeature::attribute
Q_INVOKABLE QVariant attribute(const QString &name) const
Lookup attribute value by attribute name.
Definition qgsfeature.cpp:344
QgsFeedback::isCanceled
bool isCanceled() const
Tells whether the operation has been canceled already.
Definition qgsfeedback.h:55
QgsFeedback::setProgress
void setProgress(double progress)
Sets the current progress for the feedback object.
Definition qgsfeedback.h:63
QgsField
Encapsulate a field in an attribute table or data source.
Definition qgsfield.h:56
QgsField::type
QMetaType::Type type
Definition qgsfield.h:63
QgsField::isDateOrTime
bool isDateOrTime
Definition qgsfield.h:60
QgsField::displayString
QString displayString(const QVariant &v) const
Formats string for display.
Definition qgsfield.cpp:323
QgsField::isNumeric
bool isNumeric
Definition qgsfield.h:59
QgsFields
Container of fields for a vector layer.
Definition qgsfields.h:46
QgsFields::append
bool append(const QgsField &field, Qgis::FieldOrigin origin=Qgis::FieldOrigin::Provider, int originIndex=-1)
Appends a field.
Definition qgsfields.cpp:76
QgsInterval::seconds
double seconds() const
Returns the interval duration in seconds.
Definition qgsinterval.h:264
QgsProcessingContext
Contains information about the context in which a processing algorithm is executed.
Definition qgsprocessingcontext.h:45
QgsProcessingException
Custom exception class for processing related exceptions.
Definition qgsexception.h:81
QgsProcessingFeedback
Base class for providing feedback from a processing algorithm.
Definition qgsprocessingfeedback.h:38
QgsProcessingOutputNumber
A numeric output for processing algorithms.
Definition qgsprocessingoutputs.h:392
QgsProcessingParameterFeatureSink
A feature sink output for processing algorithms.
Definition qgsprocessingparameters.h:3628
QgsProcessingParameterFeatureSource
An input feature source (such as vector layers) parameter for processing algorithms.
Definition qgsprocessingparameters.h:3466
QgsProcessingParameterField
A vector layer or feature source field parameter for processing algorithms.
Definition qgsprocessingparameters.h:3359
QgsProcessingParameterFileDestination
A generic file based destination parameter, for specifying the destination path for a file (non-map l...
Definition qgsprocessingparameters.h:3874
QgsStatisticalSummary
Calculator for summary statistics for a list of doubles.
Definition qgsstatisticalsummary.h:47
QgsStatisticalSummary::addVariant
void addVariant(const QVariant &value)
Adds a single value to the statistics calculation.
Definition qgsstatisticalsummary.cpp:107
QgsStatisticalSummary::firstQuartile
double firstQuartile() const
Returns the first quartile of the values.
Definition qgsstatisticalsummary.h:242
QgsStatisticalSummary::sum
double sum() const
Returns calculated sum of values.
Definition qgsstatisticalsummary.h:145
QgsStatisticalSummary::mean
double mean() const
Returns calculated mean of values.
Definition qgsstatisticalsummary.h:151
QgsStatisticalSummary::majority
double majority() const
Returns majority of values.
Definition qgsstatisticalsummary.h:233
QgsStatisticalSummary::countMissing
int countMissing() const
Returns the number of missing (null) values.
Definition qgsstatisticalsummary.h:140
QgsStatisticalSummary::interQuartileRange
double interQuartileRange() const
Returns the inter quartile range of the values.
Definition qgsstatisticalsummary.h:260
QgsStatisticalSummary::median
double median() const
Returns calculated median of values.
Definition qgsstatisticalsummary.h:158
QgsStatisticalSummary::minority
double minority() const
Returns minority of values.
Definition qgsstatisticalsummary.h:224
QgsStatisticalSummary::min
double min() const
Returns calculated minimum from values.
Definition qgsstatisticalsummary.h:164
QgsStatisticalSummary::stDev
double stDev() const
Returns population standard deviation.
Definition qgsstatisticalsummary.h:200
QgsStatisticalSummary::thirdQuartile
double thirdQuartile() const
Returns the third quartile of the values.
Definition qgsstatisticalsummary.h:251
QgsStatisticalSummary::count
int count() const
Returns calculated count of values.
Definition qgsstatisticalsummary.h:135
QgsStatisticalSummary::range
double range() const
Returns calculated range (difference between maximum and minimum values).
Definition qgsstatisticalsummary.h:176
QgsStatisticalSummary::max
double max() const
Returns calculated maximum from values.
Definition qgsstatisticalsummary.h:170
QgsStatisticalSummary::finalize
void finalize()
Must be called after adding all values with addValues() and before retrieving any calculated statisti...
Definition qgsstatisticalsummary.cpp:122
QgsStatisticalSummary::variety
int variety() const
Returns variety of values.
Definition qgsstatisticalsummary.h:215
QgsStringStatisticalSummary
Calculator for summary statistics and aggregates for a list of strings.
Definition qgsstringstatisticalsummary.h:44
QgsStringStatisticalSummary::max
QString max() const
Returns the maximum (non-null) string value.
Definition qgsstringstatisticalsummary.h:165
QgsStringStatisticalSummary::min
QString min() const
Returns the minimum (non-null) string value.
Definition qgsstringstatisticalsummary.h:160
QgsStringStatisticalSummary::countMissing
int countMissing() const
Returns the number of missing (null) string values.
Definition qgsstringstatisticalsummary.h:155
QgsStringStatisticalSummary::count
int count() const
Returns the calculated count of values.
Definition qgsstringstatisticalsummary.h:138
QgsStringStatisticalSummary::countDistinct
int countDistinct() const
Returns the number of distinct string values.
Definition qgsstringstatisticalsummary.h:144
QgsStringStatisticalSummary::finalize
void finalize()
Must be called after adding all strings with addString() and before retrieving any calculated string ...
Definition qgsstringstatisticalsummary.cpp:80
QgsStringStatisticalSummary::addValue
void addValue(const QVariant &value)
Adds a single variant to the statistics calculation.
Definition qgsstringstatisticalsummary.cpp:72
QgsStringStatisticalSummary::minLength
int minLength() const
Returns the minimum length of strings.
Definition qgsstringstatisticalsummary.h:170
QgsStringStatisticalSummary::maxLength
int maxLength() const
Returns the maximum length of strings.
Definition qgsstringstatisticalsummary.h:175
QgsStringStatisticalSummary::majority
QString majority() const
Returns the most common string.
Definition qgsstringstatisticalsummary.h:200
QgsStringStatisticalSummary::minority
QString minority() const
Returns the least common string.
Definition qgsstringstatisticalsummary.h:190
QgsStringStatisticalSummary::meanLength
double meanLength() const
Returns the mean length of strings.
Definition qgsstringstatisticalsummary.h:180
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