QGIS API Documentation 3.43.0-Master (e01d6d7c4c0)
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#include "qgsstatisticalsummary.h"
20#include "qgsdatetimestatisticalsummary.h"
21#include "qgsstringstatisticalsummary.h"
22
23
25
26QString QgsBasicStatisticsAlgorithm::name() const
27{
28 return QStringLiteral( "basicstatisticsforfields" );
29}
30
31QString QgsBasicStatisticsAlgorithm::displayName() const
32{
33 return QObject::tr( "Basic statistics for fields" );
34}
35
36QStringList QgsBasicStatisticsAlgorithm::tags() const
37{
38 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( ',' );
39}
40
41QString QgsBasicStatisticsAlgorithm::group() const
42{
43 return QObject::tr( "Vector analysis" );
44}
45
46QString QgsBasicStatisticsAlgorithm::groupId() const
47{
48 return QStringLiteral( "vectoranalysis" );
49}
50
51QString QgsBasicStatisticsAlgorithm::shortHelpString() const
52{
53 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." );
54}
55
56QString QgsBasicStatisticsAlgorithm::shortDescription() const
57{
58 return QObject::tr( "Generates basic statistics from the values in a field of a vector layer." );
59}
60
61QgsBasicStatisticsAlgorithm *QgsBasicStatisticsAlgorithm::createInstance() const
62{
63 return new QgsBasicStatisticsAlgorithm();
64}
65
66void QgsBasicStatisticsAlgorithm::initAlgorithm( const QVariantMap & )
67{
68 addParameter( new QgsProcessingParameterFeatureSource( QStringLiteral( "INPUT_LAYER" ), QObject::tr( "Input layer" ), QList<int>() << static_cast<int>( Qgis::ProcessingSourceType::Vector ) ) );
69 addParameter( new QgsProcessingParameterField( QStringLiteral( "FIELD_NAME" ), QObject::tr( "Field to calculate statistics on" ), QVariant(), QStringLiteral( "INPUT_LAYER" ) ) );
70 addParameter( new QgsProcessingParameterFeatureSink( QStringLiteral( "OUTPUT" ), QObject::tr( "Statistics" ), Qgis::ProcessingSourceType::Vector, QVariant(), true ) );
71 addParameter( new QgsProcessingParameterFileDestination( QStringLiteral( "OUTPUT_HTML_FILE" ), QObject::tr( "Statistics report" ), QObject::tr( "'HTML files (*.html)" ), QVariant(), true ) );
72
73 addOutput( new QgsProcessingOutputNumber( QStringLiteral( "COUNT" ), QObject::tr( "Count" ) ) );
74 addOutput( new QgsProcessingOutputNumber( QStringLiteral( "UNIQUE" ), QObject::tr( "Number of unique values" ) ) );
75 addOutput( new QgsProcessingOutputNumber( QStringLiteral( "EMPTY" ), QObject::tr( "Number of empty (null) values" ) ) );
76 addOutput( new QgsProcessingOutputNumber( QStringLiteral( "FILLED" ), QObject::tr( "Number of non-empty values" ) ) );
77 addOutput( new QgsProcessingOutputNumber( QStringLiteral( "MIN" ), QObject::tr( "Minimum value" ) ) );
78 addOutput( new QgsProcessingOutputNumber( QStringLiteral( "MAX" ), QObject::tr( "Maximum value" ) ) );
79 addOutput( new QgsProcessingOutputNumber( QStringLiteral( "MIN_LENGTH" ), QObject::tr( "Minimum length" ) ) );
80 addOutput( new QgsProcessingOutputNumber( QStringLiteral( "MAX_LENGTH" ), QObject::tr( "Maximum length" ) ) );
81 addOutput( new QgsProcessingOutputNumber( QStringLiteral( "MEAN_LENGTH" ), QObject::tr( "Mean length" ) ) );
82 addOutput( new QgsProcessingOutputNumber( QStringLiteral( "CV" ), QObject::tr( "Coefficient of Variation" ) ) );
83 addOutput( new QgsProcessingOutputNumber( QStringLiteral( "SUM" ), QObject::tr( "Sum" ) ) );
84 addOutput( new QgsProcessingOutputNumber( QStringLiteral( "MEAN" ), QObject::tr( "Mean value" ) ) );
85 addOutput( new QgsProcessingOutputNumber( QStringLiteral( "STD_DEV" ), QObject::tr( "Standard deviation" ) ) );
86 addOutput( new QgsProcessingOutputNumber( QStringLiteral( "RANGE" ), QObject::tr( "Range" ) ) );
87 addOutput( new QgsProcessingOutputNumber( QStringLiteral( "MEDIAN" ), QObject::tr( "Median" ) ) );
88 addOutput( new QgsProcessingOutputNumber( QStringLiteral( "MINORITY" ), QObject::tr( "Minority (rarest occurring value)" ) ) );
89 addOutput( new QgsProcessingOutputNumber( QStringLiteral( "MAJORITY" ), QObject::tr( "Majority (most frequently occurring value)" ) ) );
90 addOutput( new QgsProcessingOutputNumber( QStringLiteral( "FIRSTQUARTILE" ), QObject::tr( "First quartile" ) ) );
91 addOutput( new QgsProcessingOutputNumber( QStringLiteral( "THIRDQUARTILE" ), QObject::tr( "Third quartile" ) ) );
92 addOutput( new QgsProcessingOutputNumber( QStringLiteral( "IQR" ), QObject::tr( "Interquartile Range (IQR)" ) ) );
93}
94
95QVariantMap QgsBasicStatisticsAlgorithm::processAlgorithm( const QVariantMap &parameters, QgsProcessingContext &context, QgsProcessingFeedback *feedback )
96{
97 std::unique_ptr<QgsProcessingFeatureSource> source( parameterAsSource( parameters, QStringLiteral( "INPUT_LAYER" ), context ) );
98 if ( !source )
99 throw QgsProcessingException( invalidSourceError( parameters, QStringLiteral( "INPUT_LAYER" ) ) );
100
101 const QString fieldName = parameterAsString( parameters, QStringLiteral( "FIELD_NAME" ), context );
102 const int fieldIndex = source->fields().lookupField( fieldName );
103 if ( fieldIndex < 0 )
104 {
105 throw QgsProcessingException( QObject::tr( "Invalid field for statistics: “%1” does not exist" ).arg( fieldName ) );
106 }
107
108 QgsField field = source->fields().at( fieldIndex );
109
110 QString outputHtml = parameterAsFileOutput( parameters, QStringLiteral( "OUTPUT_HTML_FILE" ), context );
111
112 QgsFeatureRequest request;
113 request.setFlags( Qgis::FeatureRequestFlag::NoGeometry ).setSubsetOfAttributes( QStringList() << fieldName, source->fields() );
114 QgsFeatureIterator features = source->getFeatures( request, Qgis::ProcessingFeatureSourceFlag::SkipGeometryValidityChecks );
115 const long long count = source->featureCount();
116
117 QgsFields fields;
118 fields.append( QgsField( QStringLiteral( "count" ), QMetaType::Int ) );
119 fields.append( QgsField( QStringLiteral( "unique" ), QMetaType::Int ) );
120 fields.append( QgsField( QStringLiteral( "empty" ), QMetaType::Int ) );
121 fields.append( QgsField( QStringLiteral( "filled" ), QMetaType::Int ) );
122
123 if ( field.isNumeric() )
124 {
125 fields.append( QgsField( QStringLiteral( "min" ), QMetaType::Double ) );
126 fields.append( QgsField( QStringLiteral( "max" ), QMetaType::Double ) );
127 fields.append( QgsField( QStringLiteral( "range" ), QMetaType::Double ) );
128 fields.append( QgsField( QStringLiteral( "sum" ), QMetaType::Double ) );
129 fields.append( QgsField( QStringLiteral( "mean" ), QMetaType::Double ) );
130 fields.append( QgsField( QStringLiteral( "median" ), QMetaType::Double ) );
131 fields.append( QgsField( QStringLiteral( "stddev" ), QMetaType::Double ) );
132 fields.append( QgsField( QStringLiteral( "cv" ), QMetaType::Double ) );
133 fields.append( QgsField( QStringLiteral( "minority" ), QMetaType::Double ) );
134 fields.append( QgsField( QStringLiteral( "majority" ), QMetaType::Double ) );
135 fields.append( QgsField( QStringLiteral( "q1" ), QMetaType::Double ) );
136 fields.append( QgsField( QStringLiteral( "q3" ), QMetaType::Double ) );
137 fields.append( QgsField( QStringLiteral( "iqr" ), QMetaType::Double ) );
138 }
139 else if ( field.isDateOrTime() )
140 {
141 if ( field.type() == QMetaType::Type::QDate )
142 {
143 fields.append( QgsField( QStringLiteral( "min" ), QMetaType::QDate ) );
144 fields.append( QgsField( QStringLiteral( "max" ), QMetaType::QDate ) );
145 }
146 else if ( field.type() == QMetaType::Type::QTime )
147 {
148 fields.append( QgsField( QStringLiteral( "min" ), QMetaType::QTime ) );
149 fields.append( QgsField( QStringLiteral( "max" ), QMetaType::QTime ) );
150 }
151 else
152 {
153 fields.append( QgsField( QStringLiteral( "min" ), QMetaType::QDateTime ) );
154 fields.append( QgsField( QStringLiteral( "max" ), QMetaType::QDateTime ) );
155 }
156 fields.append( QgsField( QStringLiteral( "range" ), QMetaType::Double ) );
157 }
158 else
159 {
160 fields.append( QgsField( QStringLiteral( "min" ), QMetaType::QString ) );
161 fields.append( QgsField( QStringLiteral( "max" ), QMetaType::QString ) );
162 fields.append( QgsField( QStringLiteral( "min_length" ), QMetaType::Double ) );
163 fields.append( QgsField( QStringLiteral( "max_length" ), QMetaType::Double ) );
164 fields.append( QgsField( QStringLiteral( "mean_length" ), QMetaType::Double ) );
165 fields.append( QgsField( QStringLiteral( "minority" ), QMetaType::QString ) );
166 fields.append( QgsField( QStringLiteral( "majority" ), QMetaType::QString ) );
167 }
168
169 QString destId;
170 std::unique_ptr<QgsFeatureSink> sink( parameterAsSink( parameters, QStringLiteral( "OUTPUT" ), context, destId, fields, Qgis::WkbType::NoGeometry, QgsCoordinateReferenceSystem() ) );
171 if ( parameters.value( QStringLiteral( "OUTPUT" ) ).isValid() && !sink )
172 throw QgsProcessingException( invalidSinkError( parameters, QStringLiteral( "OUTPUT" ) ) );
173
174 QStringList data;
175 data << QObject::tr( "Analyzed field: %1" ).arg( fieldName );
176
177 QVariantMap outputs;
178
179 if ( field.isNumeric() )
180 {
181 outputs = calculateNumericStatistics( fieldIndex, features, count, sink.get(), data, feedback );
182 }
183 else if ( field.isDateOrTime() )
184 {
185 outputs = calculateDateTimeStatistics( fieldIndex, field, features, count, sink.get(), data, feedback );
186 }
187 else
188 {
189 outputs = calculateStringStatistics( fieldIndex, features, count, sink.get(), data, feedback );
190 }
191 if ( sink )
192 sink->finalize();
193
194 if ( !outputHtml.isEmpty() )
195 {
196 QFile file( outputHtml );
197 if ( file.open( QIODevice::WriteOnly | QIODevice::Truncate ) )
198 {
199 QTextStream out( &file );
200#if QT_VERSION < QT_VERSION_CHECK( 6, 0, 0 )
201 out.setCodec( "UTF-8" );
202#endif
203 out << QStringLiteral( "<html><head><meta http-equiv=\"Content-Type\" content=\"text/html;charset=utf-8\"/></head><body>\n" );
204 for ( const QString &s : data )
205 {
206 out << QStringLiteral( "<p>%1</p>" ).arg( s );
207 }
208 out << QStringLiteral( "</body></html>" );
209
210 outputs.insert( QStringLiteral( "OUTPUT_HTML_FILE" ), outputHtml );
211 }
212 }
213
214 if ( sink )
215 {
216 outputs.insert( QStringLiteral( "OUTPUT" ), destId );
217 }
218
219 return outputs;
220}
221
222QVariantMap QgsBasicStatisticsAlgorithm::calculateNumericStatistics( const int fieldIndex, QgsFeatureIterator features, const long long count, QgsFeatureSink *sink, QStringList &data, QgsProcessingFeedback *feedback )
223{
224 const double step = count > 0 ? 100.0 / count : 1;
225 long long current = 0;
226
227 QgsFeature f;
228 QgsStatisticalSummary stat;
229
230 while ( features.nextFeature( f ) )
231 {
232 if ( feedback->isCanceled() )
233 {
234 break;
235 }
236
237 stat.addVariant( f.attribute( fieldIndex ) );
238 feedback->setProgress( current * step );
239 current++;
240 }
241 stat.finalize();
242
243 const double cv = stat.mean() != 0 ? stat.stDev() / stat.mean() : 0;
244
245 QVariantMap outputs;
246 outputs.insert( QStringLiteral( "COUNT" ), stat.count() );
247 outputs.insert( QStringLiteral( "UNIQUE" ), stat.variety() );
248 outputs.insert( QStringLiteral( "EMPTY" ), stat.countMissing() );
249 outputs.insert( QStringLiteral( "FILLED" ), count - stat.countMissing() );
250 outputs.insert( QStringLiteral( "MIN" ), stat.min() );
251 outputs.insert( QStringLiteral( "MAX" ), stat.max() );
252 outputs.insert( QStringLiteral( "RANGE" ), stat.range() );
253 outputs.insert( QStringLiteral( "SUM" ), stat.sum() );
254 outputs.insert( QStringLiteral( "MEAN" ), stat.mean() );
255 outputs.insert( QStringLiteral( "MEDIAN" ), stat.median() );
256 outputs.insert( QStringLiteral( "STD_DEV" ), stat.stDev() );
257 outputs.insert( QStringLiteral( "CV" ), cv );
258 outputs.insert( QStringLiteral( "MINORITY" ), stat.minority() );
259 outputs.insert( QStringLiteral( "MAJORITY" ), stat.majority() );
260 outputs.insert( QStringLiteral( "FIRSTQUARTILE" ), stat.firstQuartile() );
261 outputs.insert( QStringLiteral( "THIRDQUARTILE" ), stat.thirdQuartile() );
262 outputs.insert( QStringLiteral( "IQR" ), stat.interQuartileRange() );
263
264 data << QObject::tr( "Count: %1" ).arg( stat.count() )
265 << QObject::tr( "Unique values: %1" ).arg( stat.variety() )
266 << QObject::tr( "NULL (missing) values: %1" ).arg( stat.countMissing() )
267 << QObject::tr( "NOT NULL (filled) values: %1" ).arg( count - stat.countMissing() )
268 << QObject::tr( "Minimum value: %1" ).arg( stat.min() )
269 << QObject::tr( "Maximum value: %1" ).arg( stat.max() )
270 << QObject::tr( "Range: %1" ).arg( stat.range() )
271 << QObject::tr( "Sum: %1" ).arg( stat.sum(), 0, 'f' )
272 << QObject::tr( "Mean value: %1" ).arg( stat.mean(), 0, 'f' )
273 << QObject::tr( "Median value: %1" ).arg( stat.median(), 0, 'f' )
274 << QObject::tr( "Standard deviation: %1" ).arg( stat.stDev(), 0, 'f', 12 )
275 << QObject::tr( "Coefficient of Variation: %1" ).arg( cv, 0, 'f' )
276 << QObject::tr( "Minority (rarest occurring value): %1" ).arg( stat.minority() )
277 << QObject::tr( "Majority (most frequently occurring value): %1" ).arg( stat.majority() )
278 << QObject::tr( "First quartile: %1" ).arg( stat.firstQuartile(), 0, 'f' )
279 << QObject::tr( "Third quartile: %1" ).arg( stat.thirdQuartile(), 0, 'f' )
280 << QObject::tr( "Interquartile Range (IQR): %1" ).arg( stat.interQuartileRange() );
281
282 if ( sink )
283 {
284 QgsFeature f;
285 f.setAttributes( QgsAttributes() << outputs.value( QStringLiteral( "COUNT" ) ) << outputs.value( QStringLiteral( "UNIQUE" ) ) << outputs.value( QStringLiteral( "EMPTY" ) ) << outputs.value( QStringLiteral( "FILLED" ) ) << outputs.value( QStringLiteral( "MIN" ) ) << outputs.value( QStringLiteral( "MAX" ) ) << outputs.value( QStringLiteral( "RANGE" ) ) << outputs.value( QStringLiteral( "SUM" ) ) << outputs.value( QStringLiteral( "MEAN" ) ) << outputs.value( QStringLiteral( "MEDIAN" ) ) << outputs.value( QStringLiteral( "STD_DEV" ) ) << outputs.value( QStringLiteral( "CV" ) ) << outputs.value( QStringLiteral( "MINORITY" ) ) << outputs.value( QStringLiteral( "MAJORITY" ) ) << outputs.value( QStringLiteral( "FIRSTQUARTILE" ) ) << outputs.value( QStringLiteral( "THIRDQUARTILE" ) ) << outputs.value( QStringLiteral( "IQR" ) ) );
286 sink->addFeature( f, QgsFeatureSink::FastInsert );
287 }
288
289 return outputs;
290}
291
292QVariantMap QgsBasicStatisticsAlgorithm::calculateDateTimeStatistics( const int fieldIndex, QgsField field, QgsFeatureIterator features, const long long count, QgsFeatureSink *sink, QStringList &data, QgsProcessingFeedback *feedback )
293{
294 const double step = count > 0 ? 100.0 / count : 1;
295 long long current = 0;
296
297 QgsFeature f;
298 QgsDateTimeStatisticalSummary stat;
299
300 while ( features.nextFeature( f ) )
301 {
302 if ( feedback->isCanceled() )
303 {
304 break;
305 }
306
307 stat.addValue( f.attribute( fieldIndex ) );
308 feedback->setProgress( current * step );
309 current++;
310 }
311 stat.finalize();
312
313 QVariantMap outputs;
314 outputs.insert( QStringLiteral( "COUNT" ), stat.count() );
315 outputs.insert( QStringLiteral( "UNIQUE" ), stat.countDistinct() );
316 outputs.insert( QStringLiteral( "EMPTY" ), stat.countMissing() );
317 outputs.insert( QStringLiteral( "FILLED" ), stat.count() - stat.countMissing() );
318 outputs.insert( QStringLiteral( "MIN" ), stat.statistic( Qgis::DateTimeStatistic::Min ) );
319 outputs.insert( QStringLiteral( "MAX" ), stat.statistic( Qgis::DateTimeStatistic::Max ) );
320 outputs.insert( QStringLiteral( "RANGE" ), stat.range().seconds() );
321
322 data << QObject::tr( "Count: %1" ).arg( stat.count() )
323 << QObject::tr( "Unique values: %1" ).arg( stat.countDistinct() )
324 << QObject::tr( "NULL (missing) values: %1" ).arg( stat.countMissing() )
325 << QObject::tr( "NOT NULL (filled) values: %1" ).arg( stat.count() - stat.countMissing() )
326 << QObject::tr( "Minimum value: %1" ).arg( field.displayString( stat.statistic( Qgis::DateTimeStatistic::Min ) ) )
327 << QObject::tr( "Maximum value: %1" ).arg( field.displayString( stat.statistic( Qgis::DateTimeStatistic::Max ) ) )
328 << QObject::tr( "Range (seconds): %1" ).arg( stat.range().seconds() );
329
330 if ( sink )
331 {
332 QgsFeature f;
333 f.setAttributes( QgsAttributes() << outputs.value( QStringLiteral( "COUNT" ) ) << outputs.value( QStringLiteral( "UNIQUE" ) ) << outputs.value( QStringLiteral( "EMPTY" ) ) << outputs.value( QStringLiteral( "FILLED" ) ) << outputs.value( QStringLiteral( "MIN" ) ) << outputs.value( QStringLiteral( "MAX" ) ) << outputs.value( QStringLiteral( "RANGE" ) ) );
334 sink->addFeature( f, QgsFeatureSink::FastInsert );
335 }
336
337 return outputs;
338}
339
340QVariantMap QgsBasicStatisticsAlgorithm::calculateStringStatistics( const int fieldIndex, QgsFeatureIterator features, const long long count, QgsFeatureSink *sink, QStringList &data, QgsProcessingFeedback *feedback )
341{
342 const double step = count > 0 ? 100.0 / count : 1;
343 long long current = 0;
344
345 QgsFeature f;
346 QgsStringStatisticalSummary stat;
347
348 while ( features.nextFeature( f ) )
349 {
350 if ( feedback->isCanceled() )
351 {
352 break;
353 }
354
355 stat.addValue( f.attribute( fieldIndex ) );
356 feedback->setProgress( current * step );
357 current++;
358 }
359 stat.finalize();
360
361 QVariantMap outputs;
362 outputs.insert( QStringLiteral( "COUNT" ), stat.count() );
363 outputs.insert( QStringLiteral( "UNIQUE" ), stat.countDistinct() );
364 outputs.insert( QStringLiteral( "EMPTY" ), stat.countMissing() );
365 outputs.insert( QStringLiteral( "FILLED" ), stat.count() - stat.countMissing() );
366 outputs.insert( QStringLiteral( "MIN" ), stat.min() );
367 outputs.insert( QStringLiteral( "MAX" ), stat.max() );
368 outputs.insert( QStringLiteral( "MIN_LENGTH" ), stat.minLength() );
369 outputs.insert( QStringLiteral( "MAX_LENGTH" ), stat.maxLength() );
370 outputs.insert( QStringLiteral( "MEAN_LENGTH" ), stat.meanLength() );
371 outputs.insert( QStringLiteral( "MINORITY" ), stat.minority() );
372 outputs.insert( QStringLiteral( "MAJORITY" ), stat.majority() );
373
374 data << QObject::tr( "Count: %1" ).arg( stat.count() )
375 << QObject::tr( "Unique values: %1" ).arg( stat.countDistinct() )
376 << QObject::tr( "NULL (missing) values: %1" ).arg( stat.countMissing() )
377 << QObject::tr( "NOT NULL (filled) values: %1" ).arg( count - stat.countMissing() )
378 << QObject::tr( "Minimum value: %1" ).arg( stat.min() )
379 << QObject::tr( "Maximum value: %1" ).arg( stat.max() )
380 << QObject::tr( "Minimum length: %1" ).arg( stat.minLength() )
381 << QObject::tr( "Maximum length: %1" ).arg( stat.maxLength() )
382 << QObject::tr( "Mean length: %1" ).arg( stat.meanLength(), 0, 'f' )
383 << QObject::tr( "Minority: %1" ).arg( stat.minority() )
384 << QObject::tr( "Majority: %1" ).arg( stat.majority() );
385
386 if ( sink )
387 {
388 QgsFeature f;
389 f.setAttributes( QgsAttributes() << outputs.value( QStringLiteral( "COUNT" ) ) << outputs.value( QStringLiteral( "UNIQUE" ) ) << outputs.value( QStringLiteral( "EMPTY" ) ) << outputs.value( QStringLiteral( "FILLED" ) ) << outputs.value( QStringLiteral( "MIN" ) ) << outputs.value( QStringLiteral( "MAX" ) ) << outputs.value( QStringLiteral( "MIN_LENGTH" ) ) << outputs.value( QStringLiteral( "MAX_LENGTH" ) ) << outputs.value( QStringLiteral( "MEAN_LENGTH" ) ) << outputs.value( QStringLiteral( "MINORITY" ) ) << outputs.value( QStringLiteral( "MAJORITY" ) ) );
390 sink->addFeature( f, QgsFeatureSink::FastInsert );
391 }
392
393 return outputs;
394}
395
Qgis::ProcessingSourceType::Vector
@ Vector
Tables (i.e. vector layers with or without geometry). When used for a sink this indicates the sink ha...
Qgis::FeatureRequestFlag::NoGeometry
@ NoGeometry
Geometry is not required. It may still be returned if e.g. required for a filter condition.
Qgis::ProcessingFeatureSourceFlag::SkipGeometryValidityChecks
@ SkipGeometryValidityChecks
Invalid geometry checks should always be skipped. This flag can be useful for algorithms which always...
Qgis::WkbType::NoGeometry
@ NoGeometry
No geometry.
Qgis::DateTimeStatistic::Max
@ Max
Maximum (latest) datetime value.
Qgis::DateTimeStatistic::Min
@ Min
Minimum (earliest) datetime value.
QgsAttributes
A vector of attributes.
Definition qgsattributes.h:60
QgsCoordinateReferenceSystem
Represents a coordinate reference system (CRS).
Definition qgscoordinatereferencesystem.h:212
QgsDateTimeStatisticalSummary
Calculator for summary statistics and aggregates for a list of datetimes.
Definition qgsdatetimestatisticalsummary.h:45
QgsDateTimeStatisticalSummary::statistic
QVariant statistic(Qgis::DateTimeStatistic stat) const
Returns the value of a specified statistic.
Definition qgsdatetimestatisticalsummary.cpp:130
QgsDateTimeStatisticalSummary::range
QgsInterval range() const
Returns the range (interval between earliest and latest non-null datetime values).
Definition qgsdatetimestatisticalsummary.cpp:156
QgsDateTimeStatisticalSummary::addValue
void addValue(const QVariant &value)
Adds a single datetime to the statistics calculation.
Definition qgsdatetimestatisticalsummary.cpp:60
QgsDateTimeStatisticalSummary::finalize
void finalize()
Must be called after adding all datetimes with addValue() and before retrieving any calculated dateti...
Definition qgsdatetimestatisticalsummary.cpp:89
QgsDateTimeStatisticalSummary::count
int count() const
Returns the calculated count of values.
Definition qgsdatetimestatisticalsummary.h:114
QgsDateTimeStatisticalSummary::countMissing
int countMissing() const
Returns the number of missing (null) datetime values.
Definition qgsdatetimestatisticalsummary.h:129
QgsDateTimeStatisticalSummary::countDistinct
int countDistinct() const
Returns the number of distinct datetime values.
Definition qgsdatetimestatisticalsummary.h:119
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:84
QgsFeatureRequest::setFlags
QgsFeatureRequest & setFlags(Qgis::FeatureRequestFlags flags)
Sets flags that affect how features will be fetched.
Definition qgsfeaturerequest.cpp:251
QgsFeatureRequest::setSubsetOfAttributes
QgsFeatureRequest & setSubsetOfAttributes(const QgsAttributeList &attrs)
Set a subset of attributes that will be fetched.
Definition qgsfeaturerequest.cpp:257
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:58
QgsFeature::setAttributes
void setAttributes(const QgsAttributes &attrs)
Sets the feature's attributes.
Definition qgsfeature.cpp:161
QgsFeature::attribute
Q_INVOKABLE QVariant attribute(const QString &name) const
Lookup attribute value by attribute name.
Definition qgsfeature.cpp:336
QgsFeedback::isCanceled
bool isCanceled() const
Tells whether the operation has been canceled already.
Definition qgsfeedback.h:53
QgsFeedback::setProgress
void setProgress(double progress)
Sets the current progress for the feedback object.
Definition qgsfeedback.h:61
QgsField
Encapsulate a field in an attribute table or data source.
Definition qgsfield.h:53
QgsField::type
QMetaType::Type type
Definition qgsfield.h:60
QgsField::isDateOrTime
bool isDateOrTime
Definition qgsfield.h:57
QgsField::displayString
QString displayString(const QVariant &v) const
Formats string for display.
Definition qgsfield.cpp:318
QgsField::isNumeric
bool isNumeric
Definition qgsfield.h:56
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:70
QgsInterval::seconds
double seconds() const
Returns the interval duration in seconds.
Definition qgsinterval.h:260
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:83
QgsProcessingFeedback
Base class for providing feedback from a processing algorithm.
Definition qgsprocessingfeedback.h:38
QgsProcessingOutputNumber
A numeric output for processing algorithms.
Definition qgsprocessingoutputs.h:370
QgsProcessingParameterFeatureSink
A feature sink output for processing algorithms.
Definition qgsprocessingparameters.h:3456
QgsProcessingParameterFeatureSource
An input feature source (such as vector layers) parameter for processing algorithms.
Definition qgsprocessingparameters.h:3294
QgsProcessingParameterField
A vector layer or feature source field parameter for processing algorithms.
Definition qgsprocessingparameters.h:3187
QgsProcessingParameterFileDestination
A generic file based destination parameter, for specifying the destination path for a file (non-map l...
Definition qgsprocessingparameters.h:3685
QgsStatisticalSummary
Calculator for summary statistics for a list of doubles.
Definition qgsstatisticalsummary.h:45
QgsStatisticalSummary::addVariant
void addVariant(const QVariant &value)
Adds a single value to the statistics calculation.
Definition qgsstatisticalsummary.cpp:102
QgsStatisticalSummary::firstQuartile
double firstQuartile() const
Returns the first quartile of the values.
Definition qgsstatisticalsummary.h:240
QgsStatisticalSummary::sum
double sum() const
Returns calculated sum of values.
Definition qgsstatisticalsummary.h:143
QgsStatisticalSummary::mean
double mean() const
Returns calculated mean of values.
Definition qgsstatisticalsummary.h:149
QgsStatisticalSummary::majority
double majority() const
Returns majority of values.
Definition qgsstatisticalsummary.h:231
QgsStatisticalSummary::countMissing
int countMissing() const
Returns the number of missing (null) values.
Definition qgsstatisticalsummary.h:138
QgsStatisticalSummary::interQuartileRange
double interQuartileRange() const
Returns the inter quartile range of the values.
Definition qgsstatisticalsummary.h:258
QgsStatisticalSummary::median
double median() const
Returns calculated median of values.
Definition qgsstatisticalsummary.h:156
QgsStatisticalSummary::minority
double minority() const
Returns minority of values.
Definition qgsstatisticalsummary.h:222
QgsStatisticalSummary::min
double min() const
Returns calculated minimum from values.
Definition qgsstatisticalsummary.h:162
QgsStatisticalSummary::stDev
double stDev() const
Returns population standard deviation.
Definition qgsstatisticalsummary.h:198
QgsStatisticalSummary::thirdQuartile
double thirdQuartile() const
Returns the third quartile of the values.
Definition qgsstatisticalsummary.h:249
QgsStatisticalSummary::count
int count() const
Returns calculated count of values.
Definition qgsstatisticalsummary.h:133
QgsStatisticalSummary::range
double range() const
Returns calculated range (difference between maximum and minimum values).
Definition qgsstatisticalsummary.h:174
QgsStatisticalSummary::max
double max() const
Returns calculated maximum from values.
Definition qgsstatisticalsummary.h:168
QgsStatisticalSummary::finalize
void finalize()
Must be called after adding all values with addValues() and before retrieving any calculated statisti...
Definition qgsstatisticalsummary.cpp:117
QgsStatisticalSummary::variety
int variety() const
Returns variety of values.
Definition qgsstatisticalsummary.h:213
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:78
QgsStringStatisticalSummary::addValue
void addValue(const QVariant &value)
Adds a single variant to the statistics calculation.
Definition qgsstringstatisticalsummary.cpp:69
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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