Merge pull request #14 from quantifyearth/mwd-min-max

Expose np maximum and minimum functions

pyproject.toml

@@ -6,7 +6,7 @@ build-backend = "setuptools.build_meta"
 
 [project]
 name = "yirgacheffe"
-version = "0.9.1"
+version = "0.9.2"
 description = "Abstraction of gdal datasets for doing basic math operations"
 readme = "README.md"
 authors = [{ name = "Michael Dales", email = "[email protected]" }]

tests/test_operators.py

@@ -908,4 +908,32 @@ def test_exp2() -> None:
 
     expected = np.exp2(data1)
     actual = result.read_array(0, 0, 4, 2)
-    assert (expected == actual).all()
+    assert (expected == actual).all()
+
+def test_minimum_layers() -> None:
+    data1 = np.array([[1.0, 2.0, 3.0, 4.0], [5.0, 2.0, 7.0, 8.0]])
+    data2 = np.array([[3.0, 2.0, 1.0, 4.0], [8.0, 2.0, 5.0, 7.0]])
+    layer1 = RasterLayer(gdal_dataset_with_data((0.0, 0.0), 0.02, data1))
+    layer2 = RasterLayer(gdal_dataset_with_data((0.0, 0.0), 0.02, data2))
+    result = RasterLayer.empty_raster_layer_like(layer1)
+
+    comp = LayerOperation.minimum(layer1, layer2)
+    comp.save(result)
+
+    expected = np.minimum(data1, data2)
+    actual = result.read_array(0, 0, 4, 2)
+    assert (expected == actual).all()
+
+def test_maximum_layers() -> None:
+    data1 = np.array([[1.0, 2.0, 3.0, 4.0], [5.0, 2.0, 7.0, 8.0]])
+    data2 = np.array([[3.0, 2.0, 1.0, 4.0], [8.0, 2.0, 5.0, 7.0]])
+    layer1 = RasterLayer(gdal_dataset_with_data((0.0, 0.0), 0.02, data1))
+    layer2 = RasterLayer(gdal_dataset_with_data((0.0, 0.0), 0.02, data2))
+    result = RasterLayer.empty_raster_layer_like(layer1)
+
+    comp = LayerOperation.maximum(layer1, layer2)
+    comp.save(result)
+
+    expected = np.maximum(data1, data2)
+    actual = result.read_array(0, 0, 4, 2)
+    assert (expected == actual).all()

yirgacheffe/operators.py

@@ -147,6 +147,22 @@ def where(cond, a, b):
             other=b
         )
 
+    @staticmethod
+    def maximum(a, b):
+        return LayerOperation(
+            a,
+            np.maximum,
+            b,
+        )
+
+    @staticmethod
+    def minimum(a, b):
+        return LayerOperation(
+            a,
+            np.minimum,
+            rhs=b,
+        )
+
     def __init__(self, lhs, operator=None, rhs=None, other=None):
         self.ystep = constants.YSTEP
 
@@ -507,3 +523,7 @@ def _eval(self, index, step):
                     result[yoffset][xoffset] = self.operator(lhs_val)
 
         return result
+
+where = LayerOperation.where
+minumum = LayerOperation.minimum
+maximum = LayerOperation.maximum