allow multiple single numbers as size for scatter

Author: ianhi

examples/interactive_scatter.ipynb

@@ -56,7 +56,7 @@
     "    return np.sin(x*tau)**2 + np.random.randn(N)*.01\n",
     "def f_y2(x, tau):\n",
     "    return np.cos(x*tau)**2 + np.random.randn(N)*.1\n",
-    "fig, ax, controls = interactive_scatter(x,[f_y1, f_y2], tau = (1, 2*np.pi, 100), c = ['blue', 'red']) "
+    "fig, ax, controls = interactive_scatter(x,[f_y1, f_y2], tau = (1, 2*np.pi, 100), c = ['blue', 'red'], s = [5, 20]) "
    ]
   },
   {
@@ -272,7 +272,7 @@
    "name": "python",
    "nbconvert_exporter": "python",
    "pygments_lexer": "ipython3",
-   "version": "3.7.8"
+   "version": "3.8.5"
   }
  },
  "nbformat": 4,

mpl_interactions/pyplot.py

@@ -1,6 +1,7 @@
 from collections import defaultdict
 from collections.abc import Callable, Iterable
 from functools import partial
+from numbers import Number
 
 import ipywidgets as widgets
 import matplotlib.widgets as mwidgets
@@ -759,11 +760,16 @@ def _prep_color(col):
         else:
             return col
 
+    def _prep_size(s):
+        if (isinstance(s, tuple) or isinstance(s, list)) and all([isinstance(es, Number) for es in s]):
+            return np.asarray(s, dtype=np.object)
+        return s
+
     X, Y, cols, sizes, edgecolors, alphas, labels = broadcast_many(
         (x, "x"),
         (y, "y"),
         (_prep_color(c), "c"),
-        (s, "s"),
+        (_prep_size(s), "s"),
         (_prep_color(edgecolors), "edgecolors"),
         (alpha, "alpha"),
         (label, "labels"),
@@ -818,7 +824,7 @@ def update(change, key, label):
                 scat.set_facecolor(c)
             if ec is not None:
                 scat.set_edgecolor(ec)
-            if s is not None:
+            if s is not None and not isinstance(s, Number):
                 scat.set_sizes(s)
             if a is not None:
                 scat.set_alpha(a)