Add list_styles

qutil/plotting/core.py

 import dataclasses
+import pathlib
 import warnings
 from contextlib import contextmanager
-from typing import Sequence, Tuple, Mapping, Any, Union
+from typing import Sequence, Tuple, Mapping, Any, Union, List
 from weakref import WeakValueDictionary
 
 import matplotlib as mpl
@@ -18,6 +19,7 @@ __all__ = [
     "plot_2d_dataframe",
     "cycle_plots",
     "update_plot",
+    "list_styles",
     "get_rwth_color_cycle",
     "rwth_color_cycle",
     "rwth_color_cycle_25",
@@ -373,6 +375,36 @@ rwth_color_cycle_100 = get_rwth_color_cycle(1)
 rwth_color_cycle = rwth_color_cycle_100
 
 
+def list_styles(include_matplotlib_styles: bool = False) -> List[str]:
+    """List available matplotlib styles.
+
+    Parameters
+    ----------
+    include_matplotlib_styles : bool, default False
+        Include the default styles that ship with ``matplotlib`` as well
+        as the custom styles in the matplotlib config directory. If
+        False, only the custom styles defined in this module are
+        listed.
+
+    Returns
+    -------
+    styles : list[str]
+        The styles such that ``plt.style.use(style)`` works for all
+        ``style`` in ``styles``.
+    """
+    custom_styles = []
+    root_path = pathlib.Path(__file__).parents[1]
+    for file in (root_path / 'plotting').glob('*.mplstyle'):
+        file = file.relative_to(root_path.parent)
+        style = '.'.join(file.parent.parts + (file.stem,))
+        custom_styles.append(style)
+
+    if include_matplotlib_styles:
+        return plt.style.available + custom_styles
+    else:
+        return custom_styles
+
+
 @dataclasses.dataclass
 class LaTeXPlotHelper:
     A4_SIZE_INCHES = (8.25, 11.75)