ENH: add support for passing arbitrary kwargs for axes.contours in an…

…notate_contour

doc/source/visualizing/callbacks.rst

@@ -247,17 +247,29 @@ Clump Finder Callback
 Overplot Contours
 ~~~~~~~~~~~~~~~~~
 
-.. function:: annotate_contour(self, field, ncont=5, factor=4, take_log=False,\
- clim=None, plot_args=None, label=False, \
- text_args=None, data_source=None)
+.. function:: annotate_contour(self, field, levels=5, *, factor=4, \
+ clim=None, take_log=None, \
+ data_source=None, label=False, \
+ text_args=None, **kwargs)
 
  (This is a proxy for
  :class:`~yt.visualization.plot_modifications.ContourCallback`.)
 
- Add contours in ``field`` to the plot. ``ncont`` governs the number of
- contours generated, ``factor`` governs the number of points used in the
- interpolation, ``take_log`` governs how it is contoured and ``clim`` gives
- the (upper, lower) limits for contouring.
+ Add contours in ``field`` to the plot. ``levels`` governs the number of
+ contours generated.
+ ``factor`` governs the number of points used in the interpolation.
+ ``clim`` gives the (upper, lower) limits for contouring.
+ ``take_log`` governs how it is contoured.
+ An alternative ``data_source`` may be supplied.
+
+ Additional keyword arguments are passed down to
+ `matplotlib.axes.Axes.contour <https://matplotlib.org/stable/api/_as_gen/matplotlib.axes.Axes.contour.html#matplotlib.axes.Axes.contour>`_
+ Note that ``negative_linestyles`` is set to ``'solid'`` by default.
+
+ Contours can be labelled by passing ``label=True``, in which case
+ it is also possible to customize text labels by supplying a dictionary
+ of additional keyword arguments as ``text_args``.
+ See `matplotlib.axes.Axes.clabel <https://matplotlib.org/stable/api/_as_gen/matplotlib.axes.Axes.clabel.html#matplotlib.axes.Axes.clabel>`_
 
 .. python-script::
 

yt/visualization/_mpl_imports.py

@@ -1,10 +1,6 @@
 # these imports are very expensive so we delay them to until they are requested
-
-import matplotlib
 from matplotlib.backend_bases import FigureCanvasBase
 from matplotlib.backends.backend_agg import FigureCanvasAgg
 from matplotlib.backends.backend_pdf import FigureCanvasPdf
 from matplotlib.backends.backend_ps import FigureCanvasPS
 from matplotlib.backends.backend_svg import FigureCanvasSVG
-
-matplotlib.rc("contour", negative_linestyle="solid")

yt/visualization/plot_modifications.py

@@ -872,12 +872,49 @@ def _transformed_field(field, data):
 
 class ContourCallback(PlotCallback):
  """
- Add contours in *field* to the plot. *levels* governs the number of
- contours generated, *factor* governs the number of points used in the
- interpolation, *take_log* governs how it is contoured and *clim* gives
- the (upper, lower) limits for contouring. An alternate data source can be
- specified with *data_source*, but by default the plot's data source will be
- queried.
+ Add contours using matplotlib.axes.Axes.contour
+
+ Arguments
+ ---------
+
+ field: field key
+ The field to draw contours of.
+
+ levels: int
+ Number of levels to be plotted.
+
+ factor: int, or tuple[int, int] (default: 16)
+ Fields are downed-sampled by this factor with respect to the background image
+ buffer size. A single integer factor will be used for both direction, but a
+ tuple of 2 integers can be passed to set x and y downsampling independently.
+
+ clim: tuple[float, float] (optional)
+ If provided, countour values will be selected within the open interval
+ [clim[0], clim[1])
+ See `take_log` for how to control the spacing between consecutive contour values.
+
+ take_log: bool (optional)
+ Coutour values will be evenly spaced on a linear scale or a log10 scale
+ depending on this parameter. By default, the value of this parameter is
+ infered from the field container attached to the dataset.
+
+ data_source: a yt data object (optional)
+ An alternative data source. By default the plot's data_source is queried.
+
+ label: bool (default: False)
+ Toggle contour labels.
+
+ text_args: dict[str, Any] (optional)
+ Used only if `label=True`. Arbitrary keyword arguments to be passed to
+ matplotlib.axes.Axes.clabel
+ In contrast to matplotlib.axes.Axes.clabel, the following
+ parameters are used by default: colors='white'
+
+ **kwargs: any additional keyword arguments will be passed
+ directly to matplotlib.axes.Axes.contour
+ In contrast to matplotlib.axes.Axes.contour, the
+ following parameters are used by default:
+ colors='black', linestyles='solid', negative_linestyles='solid'
  """
 
  _type_name = "contour"
@@ -891,15 +928,14 @@ def __init__(
  *,
  factor: Union[Tuple[int, int], int] = 4,
  clim: Optional[Tuple[float, float]] = None,
- label: bool = False,
  take_log: Optional[bool] = None,
  data_source: Optional[YTDataContainer] = None,
- plot_args: Optional[Dict[str, Any]] = None,
+ label: bool = False,
  text_args: Optional[Dict[str, Any]] = None,
+ plot_args: Optional[Dict[str, Any]] = None, # deprecated
  ncont: Optional[int] = None, # deprecated
+ **kwargs,
  ) -> None:
- def_plot_args = {"colors": "k", "linestyles": "solid"}
- def_text_args = {"colors": "w"}
  if ncont is not None:
  issue_deprecation_warning(
  "The `ncont` keyword argument is deprecated, use `levels` instead.",
@@ -914,13 +950,27 @@ def __init__(
  self.factor = _validate_factor_tuple(factor)
  self.clim = clim
  self.take_log = take_log
- if plot_args is None:
- plot_args = def_plot_args
- self.plot_args = plot_args
+
+ _plot_args = {
+ "colors": "black",
+ "linestyles": "solid",
+ "negative_linestyles": "solid",
+ }
+ if plot_args is not None:
+ issue_deprecation_warning(
+ "`plot_args` is deprecated. "
+ "You can now pass arbitrary keyword arguments instead of a dictionary.",
+ since="4.3",
+ stacklevel=5,
+ )
+ _plot_args.update(plot_args)
+ _plot_args.update(kwargs)
+ self.plot_args = _plot_args
+
  self.label = label
  if text_args is None:
- text_args = def_text_args
- self.text_args = text_args
+ text_args = {}
+ self.text_args = {"colors": "white", **text_args}
  self.data_source = data_source
 
  def __call__(self, plot) -> None:

yt/visualization/tests/test_callbacks.py

@@ -711,7 +711,7 @@ def test_contour_callback():
  factor=8,
  take_log=False,
  clim=(0.4, 0.6),
- plot_args={"linewidths": 2.0},
+ linewidths=2.0,
  label=True,
  text_args={"fontsize": "x-large"},
  )
@@ -725,7 +725,7 @@ def test_contour_callback():
  factor=8,
  take_log=False,
  clim=(0.4, 0.6),
- plot_args={"linewidths": 2.0},
+ linewidths=2.0,
  label=True,
  text_args={"fontsize": "x-large"},
  data_source=s2,
@@ -742,7 +742,8 @@ def test_contour_callback():
  take_log=False,
  clim=(1.0e-1, 1.0e1),
  label=True,
- plot_args={"colors": ("c", "w"), "linewidths": 1},
+ colors=("c", "w"),
+ linewidths=1,
  text_args={"fmt": "%1.1f"},
  )
  assert_fname(slc.save(prefix)[0])