add messages to assertion checks (#133)

segysak/_accessor.py

@@ -227,9 +227,11 @@ def coordinate_df(
     """
     cdp_x, cdp_y = ds.segysak.get_coords()
 
-    assert ds[cdp_x].dims == ds[cdp_y].dims
+    assert (
+        ds[cdp_x].dims == ds[cdp_y].dims
+    ), f"{cdp_x} and {cdp_y} vars do not have the same dims"
     dims = ds[cdp_x].dims
-    assert len(dims) == 2
+    assert len(dims) == 2, f"{cdp_x} and {cdp_y} are not 2D"
 
     df = ds[[cdp_x, cdp_y]].to_dataframe().reset_index()
     df_nona = df.dropna()
@@ -346,14 +348,16 @@ def set_dimensions(
         """
         attrs = {}
         for key, value in seisnc_dims.items():
-            assert key in DimKeyField
-            assert value in self._obj.dims
+            assert key in DimKeyField, f"{key} is not a valid dimension"
+            assert value in self._obj.dims, f"{value} is not in Dataset dims"
 
         if seisnc_dims is not None:
             attrs[AttrKeyField.dimensions] = seisnc_dims
 
         if seisnc_vert_dim is not None:
-            assert seisnc_vert_dim in self._obj.dims
+            assert (
+                seisnc_vert_dim in self._obj.dims
+            ), f"{seisnc_vert_dim} is not in Dataset dims"
             attrs[DimKeyField.samples] = seisnc_vert_dim
 
         self.store_attributes(**attrs)
@@ -410,8 +414,8 @@ def set_coords(self, seisnc_coords: Dict[Union[_CoordKeyField, str], str]):
         """
         attrs = {}
         for key, value in seisnc_coords.items():
-            assert key in CoordKeyField
-            assert value in self._obj.data_vars
+            assert key in CoordKeyField, f"{key} is not a valid Coordinate key"
+            assert value in self._obj.data_vars, f"{value} is not in Dataset variables"
 
         self.store_attributes(**seisnc_coords)
 
@@ -494,9 +498,9 @@ def calc_corner_points(self) -> List[Tuple[str, str]]:
         assert (
             self._obj[cdp_x].segysak.get_dimensions()
             == self._obj[cdp_y].segysak.get_dimensions()
-        )
+        ), f"{cdp_x} and {cdp_y} do not have the same dimensions"
         dims = self._obj[cdp_x].segysak.get_dimensions()
-        assert len(dims) <= 2
+        assert len(dims) <= 2, f"{cdp_x} and {cdp_y} are not 1D or 2D"
 
         # 3d or 2d selection (polygon vs line)
         if len(dims) == 2:

segysak/geometry.py

@@ -156,8 +156,8 @@ def get_uniform_spacing(
         Interpolated points, Interpolated extra vars: Uniform sampling using the bin_spacing hint.
     """
     points = np.asarray(points)
-    assert len(points.shape) == 2
-    assert points.shape[1] == 2
+    assert len(points.shape) == 2, f"points must be array of shape [N, 2]"
+    assert points.shape[1] == 2, f"points must be array of shape [N, 2]"
 
     segment_lengths = np.insert(np.linalg.norm(np.diff(points, axis=0), axis=1), 0, 0.0)
     segments_cum_lengths = np.cumsum(segment_lengths)

segysak/segy/_xarray_writer.py

@@ -130,7 +130,9 @@ def _create_output_trace_headers(
 
         # change numbering if dead traces
         if dead_trace_da is not None:
-            assert dead_trace_da.dtype == bool
+            assert (
+                dead_trace_da.dtype == bool
+            ), f"Dead trace map should be of type: bool"
             n_dead = dead_trace_da.sum()
             trace_numbers[:] = -1
             # use the dead_trace_da as a mask to assign trace numbering (skipping dead traces)
@@ -245,7 +247,7 @@ def to_segy(
                 to the function.
         """
         # test for bad args
-        assert data_var in ds
+        assert data_var in ds, f"Data variable '{data_var}' not found in Dataset"
 
         # process dimension arguments
         da_dims = tuple(ds[data_var].dims)
@@ -278,7 +280,7 @@ def to_segy(
         if not trace_header_map:
             trace_header_map = dict()
         for th in trace_header_map:
-            assert th in _dse
+            assert th in _dse, f"Trace header variable {th} not found in Dataset"
 
         header_vars = {
             byte: _dse[var]