adding more nodes

tests/node_tests/pixel_binning.py

@@ -0,0 +1,35 @@
+import numpy as np
+import pytest
+from tests.node_tests._shared import make_field
+
+
+def test_shape_reduction():
+    """64x64 with bin_size=2 should produce 32x32."""
+    from backend.nodes.pixel_binning import PixelBinning
+
+    node = PixelBinning()
+    field = make_field(shape=(64, 64))
+    result, = node.process(field, bin_size=2, method="mean")
+    assert result.data.shape == (32, 32)
+
+
+def test_mean_uniform():
+    """Uniform field of value 5.0 with mean binning should keep all values at 5.0."""
+    from backend.nodes.pixel_binning import PixelBinning
+
+    node = PixelBinning()
+    data = np.full((64, 64), 5.0, dtype=np.float64)
+    field = make_field(data=data)
+    result, = node.process(field, bin_size=2, method="mean")
+    assert np.allclose(result.data, 5.0)
+
+
+def test_sum_doubles():
+    """Uniform field of 1.0 with bin_size=2 and sum should give 4.0 everywhere."""
+    from backend.nodes.pixel_binning import PixelBinning
+
+    node = PixelBinning()
+    data = np.ones((64, 64), dtype=np.float64)
+    field = make_field(data=data)
+    result, = node.process(field, bin_size=2, method="sum")
+    assert np.allclose(result.data, 4.0)