Fix up pandas-indexing dependency

Author: znichollscr

README.md

@@ -38,7 +38,7 @@ Some suggested options:
   and we won't reply to any issues
 -->
 
-- prototype: the project is just starting up and the code is all prototype
+- development: the project is actively being worked on
 
 <!--- --8<-- [end:description] -->
 
@@ -89,6 +89,20 @@ The (non-locked) version of gcages can be installed with
     pip install gcages
     ```
 
+Additional dependencies can be installed using
+
+=== "pip"
+    ```sh
+    # To add the dependencies required to run processing like AR6
+    pip install 'gcages[ar6]'
+
+    # To add progress bar-related dependencies
+    pip install 'gcages[progress]'
+
+    # To add all optional dependencies
+    pip install 'gcages[full]'
+    ```
+
 ### For developers
 
 For development, we rely on [uv](https://docs.astral.sh/uv/)

pyproject.toml

@@ -42,6 +42,7 @@ Issues = "https://github.com/openscm/gcages/issues"
 [project.optional-dependencies]
 ar6 = [
     "aneris-iamc>=0.4.2 ; python_full_version >= '3.10'",
+    "pandas-indexing>=0.6.3",
     "scipy>=1.13.0",
 ]
 progress = [

requirements-docs-locked.txt

@@ -23,7 +23,7 @@ cycler==0.12.1 ; python_full_version >= '3.10'
 debugpy==1.8.11
 decorator==5.1.1
 defusedxml==0.7.1
-deprecated==1.2.18 ; python_full_version >= '3.10'
+deprecated==1.2.18
 et-xmlfile==2.0.0 ; python_full_version >= '3.10'
 exceptiongroup==1.2.2 ; python_full_version < '3.11'
 executing==2.1.0
@@ -91,7 +91,7 @@ overrides==7.7.0
 packaging==24.2
 paginate==0.5.7
 pandas==2.2.3
-pandas-indexing==0.6.3 ; python_full_version >= '3.10'
+pandas-indexing==0.6.3
 pandas-openscm==0.3.2
 pandocfilters==1.5.1
 parso==0.8.4
@@ -150,6 +150,6 @@ wcwidth==0.2.13
 webcolors==24.11.1
 webencodings==0.5.1
 websocket-client==1.8.0
-wrapt==1.17.2 ; python_full_version >= '3.10'
+wrapt==1.17.2
 xlrd==2.0.1 ; python_full_version >= '3.10'
 zipp==3.21.0 ; python_full_version < '3.10'

src/gcages/ar6/pre_processing.py

@@ -10,16 +10,11 @@
 from typing import TYPE_CHECKING, Callable
 
 import pandas as pd
-import pandas_indexing as pix  # type: ignore
 from attrs import define
 from pandas_openscm.parallelisation import ParallelOpConfig, apply_op_parallel_progress
 
 from gcages.assertions import assert_only_working_on_variable_unit_variations
-
-# from gcages.parallelisation import (
-#     assert_only_working_on_variable_unit_variations,
-#     run_parallel,
-# )
+from gcages.exceptions import MissingOptionalDependencyError
 from gcages.units_helpers import strip_pint_incompatible_characters_from_units
 
 if TYPE_CHECKING:
@@ -61,6 +56,13 @@ def add_conditional_sums(
     :
         `indf` with conditional sums added if all enabling conditions were fulfilled.
     """
+    try:
+        import pandas_indexing as pix
+    except ImportError as exc:
+        raise MissingOptionalDependencyError(
+            "add_conditional_sums", requirement="pandas_indexing"
+        ) from exc
+
     assert_only_working_on_variable_unit_variations(indf)
 
     if copy_on_entry:
@@ -121,6 +123,13 @@ def reclassify_variables(
     :
         `indf`, reclassified as needed.
     """
+    try:
+        import pandas_indexing as pix
+    except ImportError as exc:
+        raise MissingOptionalDependencyError(
+            "reclassify_variables", requirement="pandas_indexing"
+        ) from exc
+
     assert_only_working_on_variable_unit_variations(indf)
 
     if copy_on_entry:
@@ -167,6 +176,13 @@ def condtionally_remove_variables(
     :
         `indf` with variables removed according to this function's logic.
     """
+    try:
+        import pandas_indexing as pix
+    except ImportError as exc:
+        raise MissingOptionalDependencyError(
+            "condtionally_remove_variables", requirement="pandas_indexing"
+        ) from exc
+
     assert_only_working_on_variable_unit_variations(indf)
 
     if copy_on_entry:
@@ -214,6 +230,13 @@ def drop_variables_if_identical(
     :
         `indf` with variables removed according to this function's logic.
     """
+    try:
+        import pandas_indexing as pix
+    except ImportError as exc:
+        raise MissingOptionalDependencyError(
+            "drop_variables_if_identical", requirement="pandas_indexing"
+        ) from exc
+
     assert_only_working_on_variable_unit_variations(indf)
 
     if copy_on_entry:
@@ -443,6 +466,13 @@ def __call__(self, in_emissions: pd.DataFrame) -> pd.DataFrame:
         :
             Pre-processed emissions
         """
+        try:
+            import pandas_indexing as pix
+        except ImportError as exc:
+            raise MissingOptionalDependencyError(
+                "AR6PreProcessor.__call__", requirement="pandas_indexing"
+            ) from exc
+
         # TODO:
         #   - enable optional checks for:
         #       - only known variable names are in the output