Merge pull request #60277 from merydian/fix-60205

Fix QgsRasterLayer and QgsRasterBlock as_numpy methods

python/PyQt6/core/__init__.py.in

@@ -569,11 +569,15 @@ try:
          raise ValueError(f"The raster block data type '{str(self.dataType())}' is not compatible with NumPy arrays.")
       src_array = _numpy.frombuffer(self.data(), dtype=raster_dtype)
       src_array = src_array.reshape((self.height(), self.width()))
-      if not self.hasNoDataValue() or not use_masking:
-         return src_array
-      else:
-         no_data_value = self.noDataValue() if isinstance(self.noDataValue(), raster_dtype) else 0
+      if use_masking:
+         if not self.hasNoDataValue():
+      	    # Default to 0 as noDataValue if none is set
+            no_data_value = 0
+         else:
+            no_data_value = self.noDataValue()
          return _numpy.ma.masked_equal(src_array, no_data_value)
+      else:
+         return src_array
 
    QgsRasterBlock.as_numpy = _raster_block_as_numpy
 
@@ -586,7 +590,10 @@ try:
           src_array = block.as_numpy(use_masking=use_masking)
           arrays.append(src_array)
 
-      return _numpy.array(arrays)  # This converts any maskedArrays to numpy.array
+      if use_masking:
+          return _numpy.ma.stack(arrays, axis=0)
+      else:
+          return _numpy.array(arrays)
 
    QgsRasterLayer.as_numpy = _raster_layer_as_numpy
 
@@ -646,7 +653,7 @@ try:
 
 
    QgsGeometry.as_numpy = _qgsgeometry_as_numpy
-   
+
 except ModuleNotFoundError:
    def _raster_block_as_numpy(self, use_masking:bool = True):
        raise QgsNotSupportedException('QgsRasterBlock.as_numpy is not available, numpy is not installed on the system')
@@ -657,7 +664,7 @@ except ModuleNotFoundError:
        raise QgsNotSupportedException('QgsRasterLayer.as_numpy is not available, numpy is not installed on the system')
 
    QgsRasterLayer.as_numpy = _raster_layer_as_numpy
-   
+
    def _geometry_as_numpy(self):
       raise QgsNotSupportedException('QgsGeometry.as_numpy is not available, numpy is not installed on the system')
 

python/core/__init__.py.in

@@ -579,11 +579,15 @@ try:
          raise ValueError(f"The raster block data type '{str(self.dataType())}' is not compatible with NumPy arrays.")
       src_array = _numpy.frombuffer(self.data(), dtype=raster_dtype)
       src_array = src_array.reshape((self.height(), self.width()))
-      if not self.hasNoDataValue() or not use_masking:
-         return src_array
-      else:
-         no_data_value = self.noDataValue() if isinstance(self.noDataValue(), raster_dtype) else 0
+      if use_masking:
+         if not self.hasNoDataValue():
+      	    # Default to 0 as noDataValue if none is set
+            no_data_value = 0
+         else:
+            no_data_value = self.noDataValue()
          return _numpy.ma.masked_equal(src_array, no_data_value)
+      else:
+         return src_array
 
    QgsRasterBlock.as_numpy = _raster_block_as_numpy
 
@@ -596,7 +600,10 @@ try:
           src_array = block.as_numpy(use_masking=use_masking)
           arrays.append(src_array)
 
-      return _numpy.array(arrays)  # This converts any maskedArrays to numpy.array
+      if use_masking:
+          return _numpy.ma.stack(arrays, axis=0)
+      else:
+          return _numpy.array(arrays)
 
    QgsRasterLayer.as_numpy = _raster_layer_as_numpy
 

tests/src/python/test_qgsrasterblock.py

@@ -47,10 +47,12 @@ def testQgsRasterBlock(self):
         self.assertTrue((block.as_numpy() == expected_array).all())
 
         # test with noDataValue set
-        block.setNoDataValue(0)
+        block.setNoDataValue(-999)
         data = numpy.array([[numpy.nan, 2], [4, 4]])
         expected_masked_array = numpy.ma.masked_array(data, mask=numpy.isnan(data))
         self.assertTrue((block.as_numpy() == expected_masked_array).all())
+        self.assertTrue(numpy.ma.isMaskedArray(block.as_numpy()))
+        self.assertTrue(block.as_numpy().fill_value == -999)
 
         # test with noDataValue set and use_masking == False
         self.assertTrue((block.as_numpy(use_masking=False) == expected_array).all())

tests/src/python/test_qgsrasterlayer.py

@@ -17,6 +17,7 @@
 import os
 from shutil import copyfile
 
+import numpy
 import numpy as np
 from osgeo import gdal
 from qgis.PyQt.QtCore import QFileInfo, QSize, QTemporaryDir
@@ -1488,20 +1489,20 @@ def test_read_xml_crash(self):
     def test_as_numpy(self):
         layer = QgsRasterLayer(self.rpath, "raster")
         arrays = layer.as_numpy()
-        self.assertEqual(type(arrays[5]), np.ndarray)
+        self.assertTrue(numpy.ma.isMaskedArray(arrays[0]))
         self.assertEqual(arrays.shape, (9, 200, 200))
         self.assertEqual(arrays[0].dtype, np.int8)
 
         # test with bands parameter
         arrays = layer.as_numpy(bands=[1, 3])
-        self.assertEqual(type(arrays[0]), np.ndarray)
+        self.assertTrue(numpy.ma.isMaskedArray(arrays[0]))
         self.assertEqual(arrays.shape, (2, 200, 200))
         self.assertEqual(arrays[0].dtype, np.int8)
 
         path = os.path.join(unitTestDataPath("raster"), "rgb_with_mask.tif")
         layer = QgsRasterLayer(path, QFileInfo(path).baseName())
         arrays = layer.as_numpy()
-        self.assertEqual(type(arrays[0]), np.ndarray)
+        self.assertTrue(numpy.ma.isMaskedArray(arrays[0]))
         self.assertEqual(arrays.shape, (4, 150, 162))
         self.assertEqual(arrays[0].dtype, np.int8)
 
@@ -1510,9 +1511,7 @@ def test_as_numpy(self):
         )
         layer = QgsRasterLayer(path, QFileInfo(path).baseName())
         arrays = layer.as_numpy()
-        self.assertEqual(
-            type(arrays[0]), np.ndarray
-        )  # All maskedArrays are converted to numpy.array
+        self.assertTrue(numpy.ma.isMaskedArray(arrays[0]))
         self.assertEqual(arrays.shape, (1, 4, 4))
         self.assertEqual(arrays[0].dtype, np.float64)