Add size parameter to scatter artist

docs/artists_api.md

@@ -51,6 +51,7 @@
       ~Scatter.data
       ~Scatter.visible
       ~Scatter.color_indices
+      ~Scatter.size
 
    .. rubric:: Attributes Summary
 
@@ -77,6 +78,7 @@
    .. autoattribute:: data
    .. autoattribute:: visible
    .. autoattribute:: color_indices
+   .. autoattribute:: size
 
    .. rubric:: Attributes Documentation
 

src/biaplotter/_tests/test_artists.py

@@ -44,6 +44,24 @@ def on_color_indices_changed(color_indices):
     assert np.all(colors[0] == scatter.categorical_colormap(0))
     assert np.all(colors[50] == scatter.categorical_colormap(2))
 
+    # Test size property
+    scatter.size = 5.0
+    assert scatter.size == 5.0
+    sizes = scatter._scatter.get_sizes()
+    assert np.all(sizes == 5.0)
+
+    scatter.size = np.linspace(1, 10, size)
+    assert np.all(scatter.size == np.linspace(1, 10, size))
+    sizes = scatter._scatter.get_sizes()
+    assert np.all(sizes == np.linspace(1, 10, size))
+
+    # Test size reset when new data is set
+    new_data = np.random.rand(size, 2)
+    scatter.data = new_data
+    assert scatter.size == 1.0
+    sizes = scatter._scatter.get_sizes()
+    assert np.all(sizes == 1.0)
+
 
 def test_histogram2d():
     # Inputs

src/biaplotter/artists.py

@@ -128,6 +128,7 @@ def __init__(self, ax: plt.Axes = None, data: np.ndarray = None, categorical_col
         super().__init__(ax, data, categorical_colormap, color_indices)
         #: Stores the scatter plot matplotlib object
         self._scatter = None
+        self._size = 1  # Default size
         self.data = data
         self.draw()  # Initial draw of the scatter plot
 
@@ -160,7 +161,7 @@ def data(self, value: np.ndarray):
         # emit signal
         self.data_changed_signal.emit(self._data)
         if self._scatter is None:
-            self._scatter = self.ax.scatter(value[:, 0], value[:, 1])
+            self._scatter = self.ax.scatter(value[:, 0], value[:, 1], s=self._size)
             self.color_indices = 0  # Set default color index
         else:
             # If the scatter plot already exists, just update its data
@@ -176,6 +177,7 @@ def data(self, value: np.ndarray):
                 # fill with zeros where new data is larger
                 color_indices[color_indices_size:] = 0
             self.color_indices = color_indices
+        self.size = 1  # Reset size to default
         self.draw()
 
     @property
@@ -236,6 +238,27 @@ def color_indices(self, indices: np.ndarray):
         self.color_indices_changed_signal.emit(self._color_indices)
         self.draw()
 
+    @property
+    def size(self) -> float | np.ndarray:
+        """Gets or sets the size of the points in the scatter plot.
+
+        Triggers a draw idle command.
+
+        Returns
+        -------
+        size : float or (N,) np.ndarray[float]
+            size of the points in the scatter plot. Accepts a scalar or an array of floats.
+        """
+        return self._size
+
+    @size.setter
+    def size(self, value: float | np.ndarray):
+        """Sets the size of the points in the scatter plot."""
+        self._size = value
+        if self._scatter is not None:
+            self._scatter.set_sizes(np.full(len(self._data), value) if np.isscalar(value) else value)
+        self.draw()
+
     def draw(self):
         """Draws or redraws the scatter plot."""
         self.ax.figure.canvas.draw_idle()