Subgroup: Raster
Class: QgsRasterIterator¶
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class
qgis.core.
QgsRasterIterator
(input: QgsRasterInterface)¶ Bases:
sip.wrapper
Constructor for QgsRasterIterator, iterating over the specified
input
raster source.QgsRasterIterator(QgsRasterIterator)
Iterator for sequentially processing raster cells.
Methods
input
Returns the input raster interface which is being iterated over. maximumTileHeight
Returns the minimum tile width returned during iteration. maximumTileWidth
Returns the maximum tile width returned during iteration. readNextRasterPart
Fetches next part of raster data, caller takes ownership of the block and caller should delete the block. setMaximumTileHeight
Sets the minimum tile height returned during iteration. setMaximumTileWidth
Sets the maximum tile width returned during iteration. startRasterRead
Start reading of raster band. stopRasterRead
Cancels the raster iteration and resets the iterator. Signals
Attributes
DEFAULT_MAXIMUM_TILE_HEIGHT
DEFAULT_MAXIMUM_TILE_WIDTH
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DEFAULT_MAXIMUM_TILE_HEIGHT
= 2000¶
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DEFAULT_MAXIMUM_TILE_WIDTH
= 2000¶
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input
(self) → QgsRasterInterface¶ Returns the input raster interface which is being iterated over.
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maximumTileHeight
(self) → int¶ Returns the minimum tile width returned during iteration.
See also
See also
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maximumTileWidth
(self) → int¶ Returns the maximum tile width returned during iteration.
See also
See also
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readNextRasterPart
(self, bandNumber: int) → Tuple[bool, int, int, QgsRasterBlock, int, int]¶ Fetches next part of raster data, caller takes ownership of the block and caller should delete the block.
Parameters: - bandNumber – band to read
- nCols – number of columns on output device
- nRows – number of rows on output device
- block – address of block pointer
- topLeftCol – top left column
- topLeftRow – top left row
Returns: false if the last part was already returned
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setMaximumTileHeight
(self, h: int)¶ Sets the minimum tile height returned during iteration.
See also
See also
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setMaximumTileWidth
(self, w: int)¶ Sets the maximum tile width returned during iteration.
See also
See also
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startRasterRead
(self, bandNumber: int, nCols: int, nRows: int, extent: QgsRectangle, feedback: QgsRasterBlockFeedback = None)¶ Start reading of raster band. Raster data can then be retrieved by calling readNextRasterPart until it returns false.
Parameters: - bandNumber – number of raster band to read
- nCols – number of columns
- nRows – number of rows
- extent – area to read
- feedback – optional raster feedback object for cancelation/preview. Added in QGIS 3.0.
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stopRasterRead
(self, bandNumber: int)¶ Cancels the raster iteration and resets the iterator.
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