qgsstringstatisticalsummary.h

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/***************************************************************************
  qgsstringstatisticalsummary.h
  -----------------------------
  Date                 : May 2016
  Copyright            : (C) 2016 by Nyall Dawson
  Email                : nyall dot dawson at gmail dot com
 ***************************************************************************
 *                                                                         *
 *   This program is free software; you can redistribute it and/or modify  *
 *   it under the terms of the GNU General Public License as published by  *
 *   the Free Software Foundation; either version 2 of the License, or     *
 *   (at your option) any later version.                                   *
 *                                                                         *
 ***************************************************************************/
 
#ifndef QGSSTRINGSTATISTICALSUMMARY_H
#define QGSSTRINGSTATISTICALSUMMARY_H
 
#include <QSet>
#include <QVariantList>
 
#include "qgis_core.h"
#include "qgis.h"
 
/***************************************************************************
 * This class is considered CRITICAL and any change MUST be accompanied with
 * full unit tests in test_qgsstringstatisticalsummary.py.
 * See details in QEP #17
 ****************************************************************************/
 
class CORE_EXPORT QgsStringStatisticalSummary
{
  public:
 
    enum Statistic
    {
      Count = 1,  
      CountDistinct = 2,  
      CountMissing = 4,  
      Min = 8, 
      Max = 16, 
      MinimumLength = 32, 
      MaximumLength = 64, 
      MeanLength = 128, 
      Minority = 256, 
      Majority = 512, 
      All = Count | CountDistinct | CountMissing | Min | Max | MinimumLength | MaximumLength | MeanLength | Minority | Majority, 
    };
    Q_DECLARE_FLAGS( Statistics, Statistic )
 
    
    QgsStringStatisticalSummary( QgsStringStatisticalSummary::Statistics stats = QgsStringStatisticalSummary::All );
 
    Statistics statistics() const { return mStatistics; }
 
    void setStatistics( QgsStringStatisticalSummary::Statistics stats ) { mStatistics = stats; }
 
    void reset();
 
    void calculate( const QStringList &values );
 
    void calculateFromVariants( const QVariantList &values );
 
    void addString( const QString &string );
 
    void addValue( const QVariant &value );
 
    void finalize();
 
    QVariant statistic( QgsStringStatisticalSummary::Statistic stat ) const;
 
    int count() const { return mCount; }
 
    int countDistinct() const { return mValues.keys().count(); }
 
    QSet< QString > distinctValues() const;
 
    int countMissing() const { return mCountMissing; }
 
    QString min() const { return mMin; }
 
    QString max() const { return mMax; }
 
    int minLength() const { return mMinLength; }
 
    int maxLength() const { return mMaxLength; }
 
    double meanLength() const { return mMeanLength; }
 
    QString minority() const { return mMinority; }
 
    QString majority() const { return mMajority; }
 
    static QString displayName( QgsStringStatisticalSummary::Statistic statistic );
 
  private:
 
    Statistics mStatistics;
 
    int mCount;
    QMap< QString, int > mValues;
    int mCountMissing;
    QString mMin;
    QString mMax;
    int mMinLength;
    int mMaxLength;
    long mSumLengths;
    double mMeanLength;
    QString mMinority;
    QString mMajority;
 
    void testString( const QString &string );
};
 
Q_DECLARE_OPERATORS_FOR_FLAGS( QgsStringStatisticalSummary::Statistics )
 
#endif // QGSSTRINGSTATISTICALSUMMARY_H