some docstring fixes

Author: nschloe

Makefile

@@ -27,3 +27,6 @@ format:
 lint:
 	black --check .
 	flake8 .
+
+doc:
+	sphinx-build -M html doc/ build/

tikzplotlib/_cleanfigure.py

@@ -7,22 +7,26 @@
 STEP_DRAW_STYLES = ["steps-pre", "steps-post", "steps-mid"]
 
 
-def clean_figure(fig=None, target_resolution=600, scale_precision=1.0):
+def clean_figure(fig=None, target_resolution: int = 600, scale_precision: float = 1.0):
     """Cleans figure as a preparation for tikz export.
     This will minimize the number of points required for the tikz figure.
     If the figure has subplots, it will recursively clean then up.
 
     Note that this function modifies the figure directly (impure function).
 
     :param fig: Matplotlib figure handle (Default value = None)
+
     :param target_resolution: target resolution of final figure in PPI.
-        If a scalar integer is provided, it is assumed to be square in both axis.
-        If a list or an np.array is provided, it is interpreted as [H, W].
-        By default 600
+                              If a scalar integer is provided, it is assumed to be
+                              square in both axis.  If a list or an np.array is
+                              provided, it is interpreted as [H, W].
+                              By default 600
     :type target_resolution: int, list or np.array, optional
+
     :param scalePrecision: scalar value indicating precision when scaling down.
-        By default 1
+                           By default 1
     :type scalePrecision: float, optional
+
     Examples
     --------