mirror of
https://github.com/qgis/QGIS.git
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c49b5b777f
Rationale: - there was a lot of large objects passed by value, so potentially there's a speed bump from this - even for implicitly shared classes like QString/QList there's still a (small) cost for copying the objects when there's no reason to - it's the right thing to do!
44 lines
1.5 KiB
Plaintext
44 lines
1.5 KiB
Plaintext
/** \ingroup analysis
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* The QGis class that calculates raster statistics (count, sum, mean) for
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* a polygon or multipolygon layer and appends the results as attributes
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*/
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class QgsZonalStatistics
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{
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%TypeHeaderCode
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#include <qgszonalstatistics.h>
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%End
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public:
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//! Enumeration of flags that specify statistics to be calculated
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enum Statistic
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{
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Count, //!< Pixel count
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Sum, //!< Sum of pixel values
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Mean, //!< Mean of pixel values
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Median, //!< Median of pixel values
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StDev, //!< Standard deviation of pixel values
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Min, //!< Min of pixel values
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Max, //!< Max of pixel values
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Range, //!< Range of pixel values (max - min)
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Minority, //!< Minority of pixel values
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Majority, //!< Majority of pixel values
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Variety, //!< Variety (count of distinct) pixel values
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All
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};
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typedef QFlags<QgsZonalStatistics::Statistic> Statistics;
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QgsZonalStatistics( QgsVectorLayer* polygonLayer, const QString& rasterFile, const QString& attributePrefix = "", int rasterBand = 1,
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const QgsZonalStatistics::Statistics& stats = QgsZonalStatistics::Statistics( QgsZonalStatistics::Count | QgsZonalStatistics::Sum | QgsZonalStatistics::Mean) );
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~QgsZonalStatistics();
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/** Starts the calculation
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@return 0 in case of success*/
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int calculateStatistics( QProgressDialog* p );
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};
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QFlags<QgsZonalStatistics::Statistic> operator|(QgsZonalStatistics::Statistic f1, QFlags<QgsZonalStatistics::Statistic> f2);
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