Netcdf support (#337)

* add netcdf support for troposphere

* reformat for pre-commit

* remove unnecessary lines

* avoid internal `opera_utils` function

* add xarray for atmosphere test reqs

* review suggestions for optional dependencies

* remove comment

---------

Co-authored-by: mirzaees <[email protected]>
Co-authored-by: Scott Staniewicz <[email protected]>
Co-authored-by: Scott Staniewicz <[email protected]>

pyproject.toml

@@ -96,7 +96,7 @@ ignore = [
 exclude = ["scripts"]
 
 [tool.ruff.lint.per-file-ignores]
-"**/__init__.py" = ["F403"]
+"**/__init__.py" = ["F401", "F403"]
 "tests/**" = ["D", "N", "PTH"]
 "benchmarks/**" = ["D", "N", "PTH", "RUF", "ARG002"]
 

src/dolphin/_types.py

@@ -84,6 +84,7 @@ class ReferencePoint(NamedTuple):
 class TropoModel(str, Enum):
     """Enumeration representing different tropospheric models."""
 
+    ECMWF = "ECMWF"
     ERA5 = "ERA5"
     HRES = "HRES"
     ERAINT = "ERAINT"

src/dolphin/atmosphere/__init__.py

@@ -1,4 +1,33 @@
-"""Atmospheric corrections."""
+from typing import Any
 
-from .ionosphere import *
-from .troposphere import *
+from .ionosphere import estimate_ionospheric_delay
+from .troposphere import estimate_tropospheric_delay
+
+__all__ = [
+    "estimate_ionospheric_delay",
+    "estimate_tropospheric_delay",
+]
+
+
+def __getattr__(name: str) -> Any:
+    if name == "delay_from_netcdf":
+        # let's load this module lazily to avoid an ImportError
+        # for when we don't use netcdf
+        from ._netcdf import delay_from_netcdf
+
+        return delay_from_netcdf
+
+    if name in __all__:
+        return globals()[name]
+
+    errmsg = f"module {__name__!r} has no attribute {name!r}"
+    raise AttributeError(errmsg)
+
+
+def __dir__() -> list[str]:
+    try:
+        from ._netcdf import delay_from_netcdf
+    except ModuleNotFoundError:
+        return __all__
+    else:
+        return sorted([*__all__, "delay_from_netcdf"])