Set default InlineBackend to retina

doc/changelog.rst

@@ -28,7 +28,7 @@ New Features
 
   .. code-block:: python
 
-      theme(figure_size=(8, 6), dpi=100)
+     theme(figure_size=(8, 6), dpi=100)
 
   will create an `800px x 600px` image.
 
@@ -37,7 +37,7 @@ New Features
 
   .. code-block:: python
 
-      theme(plot_subtitle=element_text(size=8))
+     theme(plot_subtitle=element_text(size=8))
 
 
 Enhancements
@@ -47,6 +47,16 @@ Enhancements
   :meth:`~plotnine.ggplot.save_helper`. It gives you access to the
   matplotlib figure that will be saved to file.
 
+- When plotting with an ipython interactive backend (e.g. in a
+  jupyter notebook). The default image output is retina. You
+  do not need to run this command.
+
+  .. code-block:: python
+
+     %config InlineBackend.figure_format = "retina"
+
+  Plotnine still respects any values set the user.
+
 API Changes
 ***********
 
@@ -72,8 +82,6 @@ API Changes
 
 - Changed default font-family (san-serif) from DejaVu Sans to Helvetica.
 
-- Default dpi has changed from 100 to 300.
-
 Bug Fixes
 *********
 

plotnine/ggplot.py

@@ -25,6 +25,7 @@
 from .themes.theme import theme, theme_get
 from .utils import (
     from_inches,
+    get_ipython,
     is_data_like,
     order_as_data_mapping,
     to_inches,
@@ -762,6 +763,16 @@ class plot_context:
         exits.
     """
 
+    # Default to retina unless user chooses otherwise
+    _IPYTHON_CONFIG: dict[str, dict[str, Any]] = {
+        "InlineBackend": {
+            "figure_format": "retina",
+            "close_figures": True,
+            "print_figure_kwargs": {"bbox_inches": None},
+        }
+    }
+    _ip_config_inlinebackend: dict[str, Any] = {}
+
     def __init__(self, plot: ggplot, show: bool = False):
         self.plot = plot
         self.show = show
@@ -782,6 +793,7 @@ def __enter__(self) -> plot_context:
         )
         self.rc_context.__enter__()
         self.pd_option_context.__enter__()
+        self._enter_ipython()
         return self
 
     def __exit__(self, exc_type, exc_value, exc_traceback):
@@ -802,4 +814,35 @@ def __exit__(self, exc_type, exc_value, exc_traceback):
 
         self.rc_context.__exit__(exc_type, exc_value, exc_traceback)
         self.pd_option_context.__exit__(exc_type, exc_value, exc_traceback)
+        self._exit_ipython()
         delattr(self.plot.theme, "_targets")
+
+    def _enter_ipython(self):
+        """
+        Setup ipython parameters in for the plot
+        """
+        ip = get_ipython()
+        if not ip:
+            return
+        elif not hasattr(ip.config, "InlineBackend"):
+            return
+
+        for key, value in self._IPYTHON_CONFIG["InlineBackend"].items():
+            if key not in ip.config.InlineBackend:  # pyright: ignore
+                self._ip_config_inlinebackend[key] = key
+                ip.run_line_magic("config", f"InlineBackend.{key} = {value!r}")
+
+    def _exit_ipython(self):
+        """
+        Undo ipython parameters in for the plot
+        """
+        ip = get_ipython()
+        if not ip:
+            return
+        elif not hasattr(ip.config, "InlineBackend"):
+            return
+
+        for key in self._ip_config_inlinebackend:
+            del ip.config["InlineBackend"][key]  # pyright: ignore
+
+        self._ip_config_inlinebackend = {}

plotnine/options.py

@@ -16,7 +16,7 @@
 aspect_ratio = "auto"
 
 #: Default DPI used by the themes
-dpi = 300
+dpi = 100
 
 #: Default figure size inches
 figure_size = (640 / dpi, 480 / dpi)

plotnine/utils.py

@@ -30,6 +30,11 @@
 
     from plotnine.typing import DataLike, FloatArray, FloatArrayLike, IntArray
 
+    try:
+        from IPython.core.interactiveshell import InteractiveShell
+    except ImportError:
+        pass
+
 
 # Points and lines of equal size should give the
 # same visual diameter (for points) and thickness
@@ -1238,3 +1243,14 @@ def __enter__(self):
 
     def __exit__(self, type, value, traceback):
         return self._cm.__exit__(type, value, traceback)
+
+
+def get_ipython() -> "InteractiveShell" | None:
+    """
+    Return running IPython instance or None
+    """
+    try:
+        from IPython.core.getipython import get_ipython
+    except ImportError:
+        return None
+    return get_ipython()