QgsRasterCalculator Class Reference

Performs raster layer calculations. More...

#include <qgsrastercalculator.h>

Public Types
enum	Result {   Success = 0 , CreateOutputError = 1 , InputLayerError = 2 , Canceled = 3 ,   ParserError = 4 , MemoryError = 5 , BandError = 6 , CalculationError = 7 }
	Result of the calculation. More...

Public Member Functions
Q_DECL_DEPRECATED	QgsRasterCalculator (const QString &formulaString, const QString &outputFile, const QString &outputFormat, const QgsRectangle &outputExtent, const QgsCoordinateReferenceSystem &outputCrs, int nOutputColumns, int nOutputRows, const QVector< QgsRasterCalculatorEntry > &rasterEntries)
	QgsRasterCalculator constructor.
	QgsRasterCalculator (const QString &formulaString, const QString &outputFile, const QString &outputFormat, const QgsRectangle &outputExtent, const QgsCoordinateReferenceSystem &outputCrs, int nOutputColumns, int nOutputRows, const QVector< QgsRasterCalculatorEntry > &rasterEntries, const QgsCoordinateTransformContext &transformContext)
	QgsRasterCalculator constructor.
Q_DECL_DEPRECATED	QgsRasterCalculator (const QString &formulaString, const QString &outputFile, const QString &outputFormat, const QgsRectangle &outputExtent, int nOutputColumns, int nOutputRows, const QVector< QgsRasterCalculatorEntry > &rasterEntries)
	QgsRasterCalculator constructor.
	QgsRasterCalculator (const QString &formulaString, const QString &outputFile, const QString &outputFormat, const QgsRectangle &outputExtent, int nOutputColumns, int nOutputRows, const QVector< QgsRasterCalculatorEntry > &rasterEntries, const QgsCoordinateTransformContext &transformContext)
	QgsRasterCalculator constructor.
QString	lastError () const
	Returns a description of the last error encountered.
Result	processCalculation (QgsFeedback *feedback=nullptr)
	Starts the calculation and writes a new raster.

Detailed Description

Performs raster layer calculations.

Definition at line 76 of file qgsrastercalculator.h.

Member Enumeration Documentation

Result

enum QgsRasterCalculator::Result

Result of the calculation.

Enumerator
Success	Calculation successful.
CreateOutputError	Error creating output data file.
InputLayerError	Error reading input layer.
Canceled	User canceled calculation.
ParserError	Error parsing formula.
MemoryError	Error allocating memory for result.
BandError	Invalid band number for input.
CalculationError	Error occurred while performing calculation.

Definition at line 81 of file qgsrastercalculator.h.

Constructor & Destructor Documentation

QgsRasterCalculator() [1/4]

QgsRasterCalculator::QgsRasterCalculator	(	const QString &	formulaString,
		const QString &	outputFile,
		const QString &	outputFormat,
		const QgsRectangle &	outputExtent,
		int	nOutputColumns,
		int	nOutputRows,
		const QVector< QgsRasterCalculatorEntry > &	rasterEntries,
		const QgsCoordinateTransformContext &	transformContext
	)

QgsRasterCalculator constructor.

Parameters

formulaString	formula for raster calculation
outputFile	output file path
outputFormat	output file format
outputExtent	output extent. CRS for output is taken from first entry in rasterEntries.
nOutputColumns	number of columns in output raster
nOutputRows	number of rows in output raster
rasterEntries	list of referenced raster layers
transformContext	coordinate transformation context

Since

QGIS 3.8

Definition at line 74 of file qgsrastercalculator.cpp.

QgsRasterCalculator() [2/4]

QgsRasterCalculator::QgsRasterCalculator	(	const QString &	formulaString,
		const QString &	outputFile,
		const QString &	outputFormat,
		const QgsRectangle &	outputExtent,
		const QgsCoordinateReferenceSystem &	outputCrs,
		int	nOutputColumns,
		int	nOutputRows,
		const QVector< QgsRasterCalculatorEntry > &	rasterEntries,
		const QgsCoordinateTransformContext &	transformContext
	)

QgsRasterCalculator constructor.

Parameters

formulaString	formula for raster calculation
outputFile	output file path
outputFormat	output file format
outputExtent	output extent, CRS is specified by outputCrs parameter
outputCrs	destination CRS for output raster
nOutputColumns	number of columns in output raster
nOutputRows	number of rows in output raster
rasterEntries	list of referenced raster layers
transformContext	coordinate transformation context

Since

QGIS 3.8

Definition at line 87 of file qgsrastercalculator.cpp.

QgsRasterCalculator() [3/4]

QgsRasterCalculator::QgsRasterCalculator	(	const QString &	formulaString,
		const QString &	outputFile,
		const QString &	outputFormat,
		const QgsRectangle &	outputExtent,
		int	nOutputColumns,
		int	nOutputRows,
		const QVector< QgsRasterCalculatorEntry > &	rasterEntries
	)

QgsRasterCalculator constructor.

Parameters

formulaString	formula for raster calculation
outputFile	output file path
outputFormat	output file format
outputExtent	output extent. CRS for output is taken from first entry in rasterEntries.
nOutputColumns	number of columns in output raster
nOutputRows	number of rows in output raster
rasterEntries	list of referenced raster layers

Deprecated:

QGIS 3.8. Use the version with transformContext instead.

Definition at line 104 of file qgsrastercalculator.cpp.

QgsRasterCalculator() [4/4]

QgsRasterCalculator::QgsRasterCalculator	(	const QString &	formulaString,
		const QString &	outputFile,
		const QString &	outputFormat,
		const QgsRectangle &	outputExtent,
		const QgsCoordinateReferenceSystem &	outputCrs,
		int	nOutputColumns,
		int	nOutputRows,
		const QVector< QgsRasterCalculatorEntry > &	rasterEntries
	)

QgsRasterCalculator constructor.

Parameters

formulaString	formula for raster calculation
outputFile	output file path
outputFormat	output file format
outputExtent	output extent, CRS is specified by outputCrs parameter
outputCrs	destination CRS for output raster
nOutputColumns	number of columns in output raster
nOutputRows	number of rows in output raster
rasterEntries	list of referenced raster layers

Deprecated:

QGIS 3.8. Use the version with transformContext instead.

Definition at line 121 of file qgsrastercalculator.cpp.

Member Function Documentation

lastError()

QString QgsRasterCalculator::lastError

(

)

const

Returns a description of the last error encountered.

Since

QGIS 3.4

Definition at line 735 of file qgsrastercalculator.cpp.

processCalculation()

QgsRasterCalculator::Result QgsRasterCalculator::processCalculation

(

QgsFeedback *

feedback = nullptr

)

Starts the calculation and writes a new raster.

The optional feedback argument can be used for progress reporting and cancellation support.

Returns

QgsRasterCalculator::Success in case of success. If an error is encountered then a description of the error can be obtained by calling lastError().

Definition at line 135 of file qgsrastercalculator.cpp.

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The documentation for this class was generated from the following files:

• /build/qgis-3.40.0+99sid/src/analysis/raster/qgsrastercalculator.h
• /build/qgis-3.40.0+99sid/src/analysis/raster/qgsrastercalculator.cpp