QGIS API Documentation 3.41.0-Master (af5edcb665c)
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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#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( "Generates basic statistics from the analysis of a 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
56QgsBasicStatisticsAlgorithm *QgsBasicStatisticsAlgorithm::createInstance() const
57{
58 return new QgsBasicStatisticsAlgorithm();
59}
60
61void QgsBasicStatisticsAlgorithm::initAlgorithm( const QVariantMap & )
62{
63 addParameter( new QgsProcessingParameterFeatureSource( QStringLiteral( "INPUT_LAYER" ), QObject::tr( "Input layer" ), QList<int>() << static_cast<int>( Qgis::ProcessingSourceType::Vector ) ) );
64 addParameter( new QgsProcessingParameterField( QStringLiteral( "FIELD_NAME" ), QObject::tr( "Field to calculate statistics on" ), QVariant(), QStringLiteral( "INPUT_LAYER" ) ) );
65 addParameter( new QgsProcessingParameterFeatureSink( QStringLiteral( "OUTPUT" ), QObject::tr( "Statistics" ), Qgis::ProcessingSourceType::Vector, QVariant(), true ) );
66 addParameter( new QgsProcessingParameterFileDestination( QStringLiteral( "OUTPUT_HTML_FILE" ), QObject::tr( "Statistics report" ), QObject::tr( "'HTML files (*.html)" ), QVariant(), true ) );
67
68 addOutput( new QgsProcessingOutputNumber( QStringLiteral( "COUNT" ), QObject::tr( "Count" ) ) );
69 addOutput( new QgsProcessingOutputNumber( QStringLiteral( "UNIQUE" ), QObject::tr( "Number of unique values" ) ) );
70 addOutput( new QgsProcessingOutputNumber( QStringLiteral( "EMPTY" ), QObject::tr( "Number of empty (null) values" ) ) );
71 addOutput( new QgsProcessingOutputNumber( QStringLiteral( "FILLED" ), QObject::tr( "Number of non-empty values" ) ) );
72 addOutput( new QgsProcessingOutputNumber( QStringLiteral( "MIN" ), QObject::tr( "Minimum value" ) ) );
73 addOutput( new QgsProcessingOutputNumber( QStringLiteral( "MAX" ), QObject::tr( "Maximum value" ) ) );
74 addOutput( new QgsProcessingOutputNumber( QStringLiteral( "MIN_LENGTH" ), QObject::tr( "Minimum length" ) ) );
75 addOutput( new QgsProcessingOutputNumber( QStringLiteral( "MAX_LENGTH" ), QObject::tr( "Maximum length" ) ) );
76 addOutput( new QgsProcessingOutputNumber( QStringLiteral( "MEAN_LENGTH" ), QObject::tr( "Mean length" ) ) );
77 addOutput( new QgsProcessingOutputNumber( QStringLiteral( "CV" ), QObject::tr( "Coefficient of Variation" ) ) );
78 addOutput( new QgsProcessingOutputNumber( QStringLiteral( "SUM" ), QObject::tr( "Sum" ) ) );
79 addOutput( new QgsProcessingOutputNumber( QStringLiteral( "MEAN" ), QObject::tr( "Mean value" ) ) );
80 addOutput( new QgsProcessingOutputNumber( QStringLiteral( "STD_DEV" ), QObject::tr( "Standard deviation" ) ) );
81 addOutput( new QgsProcessingOutputNumber( QStringLiteral( "RANGE" ), QObject::tr( "Range" ) ) );
82 addOutput( new QgsProcessingOutputNumber( QStringLiteral( "MEDIAN" ), QObject::tr( "Median" ) ) );
83 addOutput( new QgsProcessingOutputNumber( QStringLiteral( "MINORITY" ), QObject::tr( "Minority (rarest occurring value)" ) ) );
84 addOutput( new QgsProcessingOutputNumber( QStringLiteral( "MAJORITY" ), QObject::tr( "Majority (most frequently occurring value)" ) ) );
85 addOutput( new QgsProcessingOutputNumber( QStringLiteral( "FIRSTQUARTILE" ), QObject::tr( "First quartile" ) ) );
86 addOutput( new QgsProcessingOutputNumber( QStringLiteral( "THIRDQUARTILE" ), QObject::tr( "Third quartile" ) ) );
87 addOutput( new QgsProcessingOutputNumber( QStringLiteral( "IQR" ), QObject::tr( "Interquartile Range (IQR)" ) ) );
88}
89
90QVariantMap QgsBasicStatisticsAlgorithm::processAlgorithm( const QVariantMap &parameters, QgsProcessingContext &context, QgsProcessingFeedback *feedback )
91{
92 std::unique_ptr<QgsProcessingFeatureSource> source( parameterAsSource( parameters, QStringLiteral( "INPUT_LAYER" ), context ) );
93 if ( !source )
94 throw QgsProcessingException( invalidSourceError( parameters, QStringLiteral( "INPUT_LAYER" ) ) );
95
96 const QString fieldName = parameterAsString( parameters, QStringLiteral( "FIELD_NAME" ), context );
97 const int fieldIndex = source->fields().lookupField( fieldName );
98 if ( fieldIndex < 0 )
99 {
100 throw QgsProcessingException( QObject::tr( "Invalid field for statistics: “%1” does not exist" ).arg( fieldName ) );
101 }
102
103 QgsField field = source->fields().at( fieldIndex );
104
105 QString outputHtml = parameterAsFileOutput( parameters, QStringLiteral( "OUTPUT_HTML_FILE" ), context );
106
107 QgsFeatureRequest request;
108 request.setFlags( Qgis::FeatureRequestFlag::NoGeometry ).setSubsetOfAttributes( QStringList() << fieldName, source->fields() );
109 QgsFeatureIterator features = source->getFeatures( request, Qgis::ProcessingFeatureSourceFlag::SkipGeometryValidityChecks );
110 const long long count = source->featureCount();
111
112 QgsFields fields;
113 fields.append( QgsField( QStringLiteral( "count" ), QMetaType::Int ) );
114 fields.append( QgsField( QStringLiteral( "unique" ), QMetaType::Int ) );
115 fields.append( QgsField( QStringLiteral( "empty" ), QMetaType::Int ) );
116 fields.append( QgsField( QStringLiteral( "filled" ), QMetaType::Int ) );
117
118 if ( field.isNumeric() )
119 {
120 fields.append( QgsField( QStringLiteral( "min" ), QMetaType::Double ) );
121 fields.append( QgsField( QStringLiteral( "max" ), QMetaType::Double ) );
122 fields.append( QgsField( QStringLiteral( "range" ), QMetaType::Double ) );
123 fields.append( QgsField( QStringLiteral( "sum" ), QMetaType::Double ) );
124 fields.append( QgsField( QStringLiteral( "mean" ), QMetaType::Double ) );
125 fields.append( QgsField( QStringLiteral( "median" ), QMetaType::Double ) );
126 fields.append( QgsField( QStringLiteral( "stddev" ), QMetaType::Double ) );
127 fields.append( QgsField( QStringLiteral( "cv" ), QMetaType::Double ) );
128 fields.append( QgsField( QStringLiteral( "minority" ), QMetaType::Double ) );
129 fields.append( QgsField( QStringLiteral( "majority" ), QMetaType::Double ) );
130 fields.append( QgsField( QStringLiteral( "q1" ), QMetaType::Double ) );
131 fields.append( QgsField( QStringLiteral( "q3" ), QMetaType::Double ) );
132 fields.append( QgsField( QStringLiteral( "iqr" ), QMetaType::Double ) );
133 }
134 else if ( field.isDateOrTime() )
135 {
136 if ( field.type() == QMetaType::Type::QDate )
137 {
138 fields.append( QgsField( QStringLiteral( "min" ), QMetaType::QDate ) );
139 fields.append( QgsField( QStringLiteral( "max" ), QMetaType::QDate ) );
140 }
141 else if ( field.type() == QMetaType::Type::QTime )
142 {
143 fields.append( QgsField( QStringLiteral( "min" ), QMetaType::QTime ) );
144 fields.append( QgsField( QStringLiteral( "max" ), QMetaType::QTime ) );
145 }
146 else
147 {
148 fields.append( QgsField( QStringLiteral( "min" ), QMetaType::QDateTime ) );
149 fields.append( QgsField( QStringLiteral( "max" ), QMetaType::QDateTime ) );
150 }
151 fields.append( QgsField( QStringLiteral( "range" ), QMetaType::Double ) );
152 }
153 else
154 {
155 fields.append( QgsField( QStringLiteral( "min" ), QMetaType::QString ) );
156 fields.append( QgsField( QStringLiteral( "max" ), QMetaType::QString ) );
157 fields.append( QgsField( QStringLiteral( "min_length" ), QMetaType::Double ) );
158 fields.append( QgsField( QStringLiteral( "max_length" ), QMetaType::Double ) );
159 fields.append( QgsField( QStringLiteral( "mean_length" ), QMetaType::Double ) );
160 fields.append( QgsField( QStringLiteral( "minority" ), QMetaType::QString ) );
161 fields.append( QgsField( QStringLiteral( "majority" ), QMetaType::QString ) );
162 }
163
164 QString destId;
165 std::unique_ptr<QgsFeatureSink> sink( parameterAsSink( parameters, QStringLiteral( "OUTPUT" ), context, destId, fields, Qgis::WkbType::NoGeometry, QgsCoordinateReferenceSystem() ) );
166 if ( parameters.value( QStringLiteral( "OUTPUT" ) ).isValid() && !sink )
167 throw QgsProcessingException( invalidSinkError( parameters, QStringLiteral( "OUTPUT" ) ) );
168
169 QStringList data;
170 data << QObject::tr( "Analyzed field: %1" ).arg( fieldName );
171
172 QVariantMap outputs;
173
174 if ( field.isNumeric() )
175 {
176 outputs = calculateNumericStatistics( fieldIndex, features, count, sink.get(), data, feedback );
177 }
178 else if ( field.isDateOrTime() )
179 {
180 outputs = calculateDateTimeStatistics( fieldIndex, field, features, count, sink.get(), data, feedback );
181 }
182 else
183 {
184 outputs = calculateStringStatistics( fieldIndex, features, count, sink.get(), data, feedback );
185 }
186 if ( sink )
187 sink->finalize();
188
189 if ( !outputHtml.isEmpty() )
190 {
191 QFile file( outputHtml );
192 if ( file.open( QIODevice::WriteOnly | QIODevice::Truncate ) )
193 {
194 QTextStream out( &file );
195#if QT_VERSION < QT_VERSION_CHECK( 6, 0, 0 )
196 out.setCodec( "UTF-8" );
197#endif
198 out << QStringLiteral( "<html><head><meta http-equiv=\"Content-Type\" content=\"text/html;charset=utf-8\"/></head><body>\n" );
199 for ( const QString &s : data )
200 {
201 out << QStringLiteral( "<p>%1</p>" ).arg( s );
202 }
203 out << QStringLiteral( "</body></html>" );
204
205 outputs.insert( QStringLiteral( "OUTPUT_HTML_FILE" ), outputHtml );
206 }
207 }
208
209 if ( sink )
210 {
211 outputs.insert( QStringLiteral( "OUTPUT" ), destId );
212 }
213
214 return outputs;
215}
216
217QVariantMap QgsBasicStatisticsAlgorithm::calculateNumericStatistics( const int fieldIndex, QgsFeatureIterator features, const long long count, QgsFeatureSink *sink, QStringList &data, QgsProcessingFeedback *feedback )
218{
219 const double step = count > 0 ? 100.0 / count : 1;
220 long long current = 0;
221
222 QgsFeature f;
223 QgsStatisticalSummary stat;
224
225 while ( features.nextFeature( f ) )
226 {
227 if ( feedback->isCanceled() )
228 {
229 break;
230 }
231
232 stat.addVariant( f.attribute( fieldIndex ) );
233 feedback->setProgress( current * step );
234 current++;
235 }
236 stat.finalize();
237
238 const double cv = stat.mean() != 0 ? stat.stDev() / stat.mean() : 0;
239
240 QVariantMap outputs;
241 outputs.insert( QStringLiteral( "COUNT" ), stat.count() );
242 outputs.insert( QStringLiteral( "UNIQUE" ), stat.variety() );
243 outputs.insert( QStringLiteral( "EMPTY" ), stat.countMissing() );
244 outputs.insert( QStringLiteral( "FILLED" ), count - stat.countMissing() );
245 outputs.insert( QStringLiteral( "MIN" ), stat.min() );
246 outputs.insert( QStringLiteral( "MAX" ), stat.max() );
247 outputs.insert( QStringLiteral( "RANGE" ), stat.range() );
248 outputs.insert( QStringLiteral( "SUM" ), stat.sum() );
249 outputs.insert( QStringLiteral( "MEAN" ), stat.mean() );
250 outputs.insert( QStringLiteral( "MEDIAN" ), stat.median() );
251 outputs.insert( QStringLiteral( "STD_DEV" ), stat.stDev() );
252 outputs.insert( QStringLiteral( "CV" ), cv );
253 outputs.insert( QStringLiteral( "MINORITY" ), stat.minority() );
254 outputs.insert( QStringLiteral( "MAJORITY" ), stat.majority() );
255 outputs.insert( QStringLiteral( "FIRSTQUARTILE" ), stat.firstQuartile() );
256 outputs.insert( QStringLiteral( "THIRDQUARTILE" ), stat.thirdQuartile() );
257 outputs.insert( QStringLiteral( "IQR" ), stat.interQuartileRange() );
258
259 data << QObject::tr( "Count: %1" ).arg( stat.count() )
260 << QObject::tr( "Unique values: %1" ).arg( stat.variety() )
261 << QObject::tr( "NULL (missing) values: %1" ).arg( stat.countMissing() )
262 << QObject::tr( "NOT NULL (filled) values: %1" ).arg( count - stat.countMissing() )
263 << QObject::tr( "Minimum value: %1" ).arg( stat.min() )
264 << QObject::tr( "Maximum value: %1" ).arg( stat.max() )
265 << QObject::tr( "Range: %1" ).arg( stat.range() )
266 << QObject::tr( "Sum: %1" ).arg( stat.sum(), 0, 'f' )
267 << QObject::tr( "Mean value: %1" ).arg( stat.mean(), 0, 'f' )
268 << QObject::tr( "Median value: %1" ).arg( stat.median(), 0, 'f' )
269 << QObject::tr( "Standard deviation: %1" ).arg( stat.stDev(), 0, 'f', 12 )
270 << QObject::tr( "Coefficient of Variation: %1" ).arg( cv, 0, 'f' )
271 << QObject::tr( "Minority (rarest occurring value): %1" ).arg( stat.minority() )
272 << QObject::tr( "Majority (most frequently occurring value): %1" ).arg( stat.majority() )
273 << QObject::tr( "First quartile: %1" ).arg( stat.firstQuartile(), 0, 'f' )
274 << QObject::tr( "Third quartile: %1" ).arg( stat.thirdQuartile(), 0, 'f' )
275 << QObject::tr( "Interquartile Range (IQR): %1" ).arg( stat.interQuartileRange() );
276
277 if ( sink )
278 {
279 QgsFeature f;
280 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" ) ) );
281 sink->addFeature( f, QgsFeatureSink::FastInsert );
282 }
283
284 return outputs;
285}
286
287QVariantMap QgsBasicStatisticsAlgorithm::calculateDateTimeStatistics( const int fieldIndex, QgsField field, QgsFeatureIterator features, const long long count, QgsFeatureSink *sink, QStringList &data, QgsProcessingFeedback *feedback )
288{
289 const double step = count > 0 ? 100.0 / count : 1;
290 long long current = 0;
291
292 QgsFeature f;
293 QgsDateTimeStatisticalSummary stat;
294
295 while ( features.nextFeature( f ) )
296 {
297 if ( feedback->isCanceled() )
298 {
299 break;
300 }
301
302 stat.addValue( f.attribute( fieldIndex ) );
303 feedback->setProgress( current * step );
304 current++;
305 }
306 stat.finalize();
307
308 QVariantMap outputs;
309 outputs.insert( QStringLiteral( "COUNT" ), stat.count() );
310 outputs.insert( QStringLiteral( "UNIQUE" ), stat.countDistinct() );
311 outputs.insert( QStringLiteral( "EMPTY" ), stat.countMissing() );
312 outputs.insert( QStringLiteral( "FILLED" ), stat.count() - stat.countMissing() );
313 outputs.insert( QStringLiteral( "MIN" ), stat.statistic( Qgis::DateTimeStatistic::Min ) );
314 outputs.insert( QStringLiteral( "MAX" ), stat.statistic( Qgis::DateTimeStatistic::Max ) );
315 outputs.insert( QStringLiteral( "RANGE" ), stat.range().seconds() );
316
317 data << QObject::tr( "Count: %1" ).arg( stat.count() )
318 << QObject::tr( "Unique values: %1" ).arg( stat.countDistinct() )
319 << QObject::tr( "NULL (missing) values: %1" ).arg( stat.countMissing() )
320 << QObject::tr( "NOT NULL (filled) values: %1" ).arg( stat.count() - stat.countMissing() )
321 << QObject::tr( "Minimum value: %1" ).arg( field.displayString( stat.statistic( Qgis::DateTimeStatistic::Min ) ) )
322 << QObject::tr( "Maximum value: %1" ).arg( field.displayString( stat.statistic( Qgis::DateTimeStatistic::Max ) ) )
323 << QObject::tr( "Range (seconds): %1" ).arg( stat.range().seconds() );
324
325 if ( sink )
326 {
327 QgsFeature f;
328 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" ) ) );
329 sink->addFeature( f, QgsFeatureSink::FastInsert );
330 }
331
332 return outputs;
333}
334
335QVariantMap QgsBasicStatisticsAlgorithm::calculateStringStatistics( const int fieldIndex, QgsFeatureIterator features, const long long count, QgsFeatureSink *sink, QStringList &data, QgsProcessingFeedback *feedback )
336{
337 const double step = count > 0 ? 100.0 / count : 1;
338 long long current = 0;
339
340 QgsFeature f;
341 QgsStringStatisticalSummary stat;
342
343 while ( features.nextFeature( f ) )
344 {
345 if ( feedback->isCanceled() )
346 {
347 break;
348 }
349
350 stat.addValue( f.attribute( fieldIndex ) );
351 feedback->setProgress( current * step );
352 current++;
353 }
354 stat.finalize();
355
356 QVariantMap outputs;
357 outputs.insert( QStringLiteral( "COUNT" ), stat.count() );
358 outputs.insert( QStringLiteral( "UNIQUE" ), stat.countDistinct() );
359 outputs.insert( QStringLiteral( "EMPTY" ), stat.countMissing() );
360 outputs.insert( QStringLiteral( "FILLED" ), stat.count() - stat.countMissing() );
361 outputs.insert( QStringLiteral( "MIN" ), stat.min() );
362 outputs.insert( QStringLiteral( "MAX" ), stat.max() );
363 outputs.insert( QStringLiteral( "MIN_LENGTH" ), stat.minLength() );
364 outputs.insert( QStringLiteral( "MAX_LENGTH" ), stat.maxLength() );
365 outputs.insert( QStringLiteral( "MEAN_LENGTH" ), stat.meanLength() );
366 outputs.insert( QStringLiteral( "MINORITY" ), stat.minority() );
367 outputs.insert( QStringLiteral( "MAJORITY" ), stat.majority() );
368
369 data << QObject::tr( "Count: %1" ).arg( stat.count() )
370 << QObject::tr( "Unique values: %1" ).arg( stat.countDistinct() )
371 << QObject::tr( "NULL (missing) values: %1" ).arg( stat.countMissing() )
372 << QObject::tr( "NOT NULL (filled) values: %1" ).arg( count - stat.countMissing() )
373 << QObject::tr( "Minimum value: %1" ).arg( stat.min() )
374 << QObject::tr( "Maximum value: %1" ).arg( stat.max() )
375 << QObject::tr( "Minimum length: %1" ).arg( stat.minLength() )
376 << QObject::tr( "Maximum length: %1" ).arg( stat.maxLength() )
377 << QObject::tr( "Mean length: %1" ).arg( stat.meanLength(), 0, 'f' )
378 << QObject::tr( "Minority: %1" ).arg( stat.minority() )
379 << QObject::tr( "Majority: %1" ).arg( stat.majority() );
380
381 if ( sink )
382 {
383 QgsFeature f;
384 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" ) ) );
385 sink->addFeature( f, QgsFeatureSink::FastInsert );
386 }
387
388 return outputs;
389}
390
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
This class 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
This class 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:317
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:3448
QgsProcessingParameterFeatureSource
An input feature source (such as vector layers) parameter for processing algorithms.
Definition qgsprocessingparameters.h:3286
QgsProcessingParameterField
A vector layer or feature source field parameter for processing algorithms.
Definition qgsprocessingparameters.h:3179
QgsProcessingParameterFileDestination
A generic file based destination parameter, for specifying the destination path for a file (non-map l...
Definition qgsprocessingparameters.h:3677
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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