Rename plot_transect with plot_cross_section (#65)

* Rename plot_transect with plot_cross_section

* Define cross_section object and redefine transect

* Fix cross-section issues

.pre-commit-config.yaml

@@ -12,7 +12,7 @@ repos:
       - id: check-ast
       - id: check-added-large-files
   - repo: https://github.com/astral-sh/ruff-pre-commit
-    rev: v0.5.7
+    rev: v0.6.2
     hooks:
       - id: ruff
         args: [--fix]

gpm/accessor/methods.py

@@ -239,14 +239,32 @@ def collocate(
             decode_cf=decode_cf,
         )
 
-    #### Transect utility
+    #### Transect/Trajectory utility
+
+    @auto_wrap_docstring
+    def extract_at_points(
+        self,
+        points,
+        method="nearest",
+        new_dim="points",
+    ):
+        from gpm.utils.manipulations import extract_at_points
+
+        return extract_at_points(
+            self._obj,
+            points=points,
+            method=method,
+            new_dim=new_dim,
+        )
+
     @auto_wrap_docstring
     def extract_transect_between_points(
         self,
         start_point,
         end_point,
         steps=100,
         method="linear",
+        new_dim="transect",
     ):
         from gpm.utils.manipulations import extract_transect_between_points
 
@@ -256,6 +274,7 @@ def extract_transect_between_points(
             end_point=end_point,
             steps=steps,
             method=method,
+            new_dim=new_dim,
         )
 
     @auto_wrap_docstring
@@ -266,6 +285,7 @@ def extract_transect_around_point(
         distance,
         steps=100,
         method="linear",
+        new_dim="transect",
     ):
         from gpm.utils.manipulations import extract_transect_around_point
 
@@ -276,20 +296,23 @@ def extract_transect_around_point(
             distance=distance,
             steps=steps,
             method=method,
+            new_dim=new_dim,
         )
 
     @auto_wrap_docstring
-    def extract_transect_along_trajectory(
+    def extract_transect_at_points(
         self,
         points,
         method="linear",
+        new_dim="transect",
     ):
-        from gpm.utils.manipulations import extract_transect_along_trajectory
+        from gpm.utils.manipulations import extract_transect_at_points
 
-        return extract_transect_along_trajectory(
+        return extract_transect_at_points(
             self._obj,
             points=points,
             method=method,
+            new_dim=new_dim,
         )
 
     #### Range subset utility
@@ -841,7 +864,7 @@ def plot_image(
         )
 
     @auto_wrap_docstring
-    def plot_transect(
+    def plot_cross_section(
         self,
         variable,
         ax=None,
@@ -854,9 +877,9 @@ def plot_transect(
         cbar_kwargs=None,
         **plot_kwargs,
     ):
-        from gpm.visualization.cross_section import plot_transect
+        from gpm.visualization.cross_section import plot_cross_section
 
-        return plot_transect(
+        return plot_cross_section(
             self._obj[variable],
             ax=ax,
             x=x,
@@ -1053,7 +1076,7 @@ def plot_image(
         )
 
     @auto_wrap_docstring
-    def plot_transect(
+    def plot_cross_section(
         self,
         ax=None,
         x=None,
@@ -1065,9 +1088,9 @@ def plot_transect(
         cbar_kwargs=None,
         **plot_kwargs,
     ):
-        from gpm.visualization.cross_section import plot_transect
+        from gpm.visualization.cross_section import plot_cross_section
 
-        return plot_transect(
+        return plot_cross_section(
             self._obj,
             ax=ax,
             x=x,

gpm/checks.py

@@ -69,14 +69,20 @@ def get_frequency_dimension(xr_obj):
 
 def get_vertical_dimension(xr_obj):
     """Return the name of the available vertical dimension."""
-    return np.array(VERTICAL_DIMS)[np.isin(VERTICAL_DIMS, list(xr_obj.dims))].tolist()
+    vertical_dim = np.array(VERTICAL_DIMS)[np.isin(VERTICAL_DIMS, list(xr_obj.dims))].tolist()
+    if len(vertical_dim) > 1:
+        raise ValueError(f"Only one vertical dimension is allowed. Got {vertical_dim}.")
+    return vertical_dim
 
 
 def get_spatial_dimensions(xr_obj):
     """Return the name of the available spatial dimensions."""
     dims = list(xr_obj.dims)
     flattened_spatial_dims = list(chain.from_iterable(SPATIAL_DIMS))
-    return np.array(flattened_spatial_dims)[np.isin(flattened_spatial_dims, dims)].tolist()
+    spatial_dimensions = np.array(flattened_spatial_dims)[np.isin(flattened_spatial_dims, dims)].tolist()
+    if len(spatial_dimensions) > 2:
+        raise ValueError(f"Only two horizontal spatial dimensions are allowed. Got {spatial_dimensions}.")
+    return spatial_dimensions
 
 
 def _has_spatial_dim_dataarray(da, strict):
@@ -230,9 +236,8 @@ def _is_expected_spatial_dims(spatial_dims):
 def is_orbit(xr_obj):
     """Check whether the xarray object is a GPM ORBIT.
 
-    An ORBIT transect or nadir view is considered ORBIT.
-    An ORBIT object must have the coordinates available !
-
+    An ORBIT cross-section (nadir view) or transect is considered ORBIT.
+    An ORBIT object must have the coordinates available.
     """
     from gpm.dataset.crs import _get_swath_dim_coords
 
@@ -304,8 +309,8 @@ def _is_spatial_3d_dataarray(da, strict):
     return True
 
 
-def _is_transect_dataarray(da, strict):
-    """Check if the xarray.DataArray is a spatial 3D array."""
+def _is_cross_section_dataarray(da, strict):
+    """Check if the xarray.DataArray is a cross-section array."""
     spatial_dims = list(get_spatial_dimensions(da))
     if len(spatial_dims) != 1:
         return False
@@ -320,6 +325,16 @@ def _is_transect_dataarray(da, strict):
     return True
 
 
+def _is_transect_dataarray(da, strict):
+    """Check if the xarray.DataArray is a transect array."""
+    spatial_dims = list(get_spatial_dimensions(da))
+    if len(spatial_dims) != 1:
+        return False
+    if strict and len(da.dims) != 1:  # noqa
+        return False
+    return True
+
+
 def _check_dataarrays_condition(condition, ds, strict):
     if not ds:  # Empty dataset (no variables)
         return False
@@ -339,8 +354,13 @@ def _is_spatial_3d_dataset(ds, strict):
     return _check_dataarrays_condition(_is_spatial_3d_dataarray, ds=ds, strict=strict)
 
 
+def _is_cross_section_dataset(ds, strict):
+    """Check if all xarray.DataArrays of a xarray.Dataset are cross-section objects."""
+    return _check_dataarrays_condition(_is_cross_section_dataarray, ds=ds, strict=strict)
+
+
 def _is_transect_dataset(ds, strict):
-    """Check if all xarray.DataArrays of a xarray.Dataset are transect objects."""
+    """Check if all xarray.DataArrays of a xarray.Dataset are transects objects."""
     return _check_dataarrays_condition(_is_transect_dataarray, ds=ds, strict=strict)
 
 
@@ -376,13 +396,31 @@ def is_spatial_3d(xr_obj, strict=True, squeeze=True):
     )
 
 
-def is_transect(xr_obj, strict=True, squeeze=True):
-    """Check if the xarray.DataArray or xarray.Dataset is a transect object.
+def is_cross_section(xr_obj, strict=True, squeeze=True):
+    """Check if the xarray.DataArray or xarray.Dataset is a cross-section object.
 
     If ``squeeze=True`` (default), dimensions of size=1 are removed prior testing.
     If ``strict=True``  (default), the xarray.DataArray must have just the
     vertical dimension and a horizontal dimension.
-    If ``strict=False`` , the xarray.DataArray can also have additional dimensions.
+    If ``strict=False`` , the xarray.DataArray can have additional dimensions but only
+    a single horizontal and vertical dimension.
+    """
+    return _check_xarray_conditions(
+        _is_cross_section_dataarray,
+        _is_cross_section_dataset,
+        xr_obj=xr_obj,
+        strict=strict,
+        squeeze=squeeze,
+    )
+
+
+def is_transect(xr_obj, strict=True, squeeze=True):
+    """Check if the xarray.DataArray or xarray.Dataset is a transect object.
+
+    If ``squeeze=True`` (default), dimensions of size=1 are removed prior testing.
+    If ``strict=True``  (default), the xarray.DataArray must have just an horizontal dimension.
+    If ``strict=False`` , the xarray.DataArray can have additional dimensions but only a single
+    horizontal dimension.
     """
     return _check_xarray_conditions(
         _is_transect_dataarray,
@@ -449,16 +487,29 @@ def check_is_spatial_3d(xr_obj, strict=True, squeeze=True):
         raise ValueError("Expecting a 3D GPM field.")
 
 
-def check_is_transect(xr_obj, strict=True, squeeze=True):
-    """Check if the xarray.DataArray or xarray.Dataset is a transect.
+def check_is_cross_section(xr_obj, strict=True, squeeze=True):
+    """Check if the xarray.DataArray or xarray.Dataset is a cross-section.
 
     If ``squeeze=True`` (default), dimensions of size=1 are removed prior testing.
     If ``strict=True``  (default), the xarray.DataArray must have just the
     vertical dimension and a horizontal dimension.
-    If ``strict=False`` , the xarray.DataArray can also have additional dimensions.
+    If ``strict=False`` , the xarray.DataArray can also have additional dimensions,
+    but only a single vertical and horizontal dimension.
+    """
+    if not is_cross_section(xr_obj, strict=strict, squeeze=squeeze):
+        raise ValueError("Expecting a cross-section extracted from a 3D GPM field.")
+
+
+def check_is_transect(xr_obj, strict=True, squeeze=True):
+    """Check if the xarray.DataArray or xarray.Dataset is a transect.
+
+    If ``squeeze=True`` (default), dimensions of size=1 are removed prior testing.
+    If ``strict=True``  (default), the xarray.DataArray must have just an horizontal dimension.
+    If ``strict=False`` , the xarray.DataArray can also have additional dimensions,
+    but only an horizontal dimension.
     """
     if not is_transect(xr_obj, strict=strict, squeeze=squeeze):
-        raise ValueError("Expecting a transect of a 3D GPM field.")
+        raise ValueError("Expecting a transect object.")
 
 
 def check_has_vertical_dim(xr_obj, strict=False, squeeze=True):
@@ -523,16 +574,26 @@ def get_spatial_3d_variables(ds, strict=False, squeeze=True):
     return sorted(variables)
 
 
-def get_transect_variables(ds, strict=False, squeeze=True):
-    """Get list of xarray.Dataset trasect variables.
+def get_cross_section_variables(ds, strict=False, squeeze=True):
+    """Get list of xarray.Dataset cross-section variables.
 
-    If ``strict=False`` (default), the potential variables for which a transect can be derived.
-    If ``strict=True``, the variables that are already provide a transect.
+    If ``strict=False`` (default), the potential variables for which a strict cross-section can be derived.
+    If ``strict=True``, the variables that are already a cross-section.
     """
-    variables = [var for var in get_dataset_variables(ds) if is_transect(ds[var], strict=strict, squeeze=squeeze)]
+    variables = [var for var in get_dataset_variables(ds) if is_cross_section(ds[var], strict=strict, squeeze=squeeze)]
     return sorted(variables)
 
 
+# def get_transect_variables(ds, strict=False, squeeze=True):
+#     """Get list of xarray.Dataset transect variables.
+
+#     If ``strict=False`` (default), the potential variables for which a strict transect can be derived.
+#     If ``strict=True``, the variables that are already a transect.
+#     """
+#     variables = [var for var in get_dataset_variables(ds) if is_transect(ds[var], strict=strict, squeeze=squeeze)]
+#     return sorted(variables)
+
+
 def get_vertical_variables(ds):
     """Get list of xarray.Dataset variables with vertical dimension."""
     variables = [var for var in get_dataset_variables(ds) if has_vertical_dim(ds[var], strict=False, squeeze=True)]

gpm/dataset/dimensions.py

@@ -90,11 +90,12 @@
 }
 
 SPATIAL_DIMS = [
-    ["transect"],
     ["along_track", "cross_track"],
     ["lat", "lon"],
     ["latitude", "longitude"],
     ["x", "y"],  # compatibility with satpy/gpm_geo i.e.
+    ["transect"],
+    ["trajectory"],
     ["beam"],  # when stacking 2D spatial dims
     ["pixel"],  # when stacking 2D spatial dims
 ]

gpm/io/download.py

@@ -264,8 +264,7 @@ def run(commands, n_threads=10, progress_bar=True, verbose=True):
     """
     from tqdm import tqdm
 
-    if n_threads < 1:
-        n_threads = 1
+    n_threads = max(n_threads, 1)
     n_threads = min(n_threads, 10)
     n_cmds = len(commands)