Merge pull request #69 from earth-chris/sample-raster-nodata

fix `sample_raster` nodata for certain rasters
earth-chris · Oct 21, 2022 · db72c1a · db72c1a
2 parents f3fc980 + 3be990c
commit db72c1a
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diff --git a/elapid/__version__.py b/elapid/__version__.py
@@ -1 +1 @@
-"0.3.16"
+"0.3.17"
diff --git a/elapid/geo.py b/elapid/geo.py
@@ -116,8 +116,17 @@ def sample_raster(raster_path: str, count: int, nodata: float = None, ignore_mas
  with rio.open(raster_path) as src:
 
  if src.nodata is None or ignore_mask:
- xmin, ymin, xmax, ymax = src.bounds
- xy = np.random.uniform((xmin, ymin), (xmax, ymax), (count, 2))
+ if nodata is None:
+ xmin, ymin, xmax, ymax = src.bounds
+ xy = np.random.uniform((xmin, ymin), (xmax, ymax), (count, 2))
+ else:
+ data = src.read(1)
+ mask = data != nodata
+ rows, cols = np.where(mask)
+ samples = np.random.randint(0, len(rows), count)
+ xy = np.zeros((count, 2))
+ for i, sample in enumerate(samples):
+ xy[i] = src.xy(rows[sample], cols[sample])
 
  else:
  if nodata is None: