adding reclass_masked_values method to Raster class

fauxgeo/raster.py

@@ -751,6 +751,13 @@ def resize_pixels(self, pixel_size, resample_method):
 
         return Raster.from_tempfile(output_uri)
 
+    def reclass_masked_values(self, mask_raster, new_value):
+        def reclass_masked_closure(nodata):
+            def reclass(x, y):
+                return np.where((np.not_equal(y, 0)), x, new_value)
+            return reclass
+        return self.local_op(mask_raster, reclass_masked_closure)
+
     def sample_from_raster(self, raster):
         '''way too slow!'''
         shape = self.get_shape()

tests/test_raster.py

@@ -6,6 +6,8 @@
 ----------------------------------
 
 Tests for Raster class.
+
+python -m unittest test_raster
 """
 
 import unittest
@@ -261,5 +263,24 @@ def test_resize_pixels(self):
         b = a.resize_pixels(0.5, 'nearest')
         assert(b.get_shape() == (8, 8))
 
+class TestRasterReclassMaskedValues(unittest.TestCase):
+    def setUp(self):
+        self.shape = (4, 4)
+        self.array = np.ones(self.shape)
+        self.affine = Affine(1, 0, 0, 0, -1, 4)
+        self.proj = 4326
+        self.datatype = gdal.GDT_Float64
+        self.nodata_val = -9999
+        self.factory = RasterFactory(
+            self.proj, self.datatype, self.nodata_val, *self.shape, affine=self.affine)
+
+    def test_reclass_masked_values(self):
+        new_value = 20
+        masked_raster = self.factory.alternating(0, 1.0)
+        raster = self.factory.uniform(np.nan)
+        new_raster = raster.reclass_masked_values(masked_raster, new_value)
+        assert(new_raster.get_band(1)[0, 0] == new_value)
+
+
 if __name__ == '__main__':
     unittest.main()