From abd89682951a60c6babc4670691991f49d621341 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Mario=20E=2E=20Vald=C3=A9s-Tresanco?=
 <46581661+marioernestovaldes@users.noreply.github.com>
Date: Wed, 18 Jun 2025 15:06:46 -0600
Subject: [PATCH] [dynamicviz] cap alpha heuristic

---
 dynamicviz/viz.py | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/dynamicviz/viz.py b/dynamicviz/viz.py
index c341716..5980619 100644
--- a/dynamicviz/viz.py
+++ b/dynamicviz/viz.py
@@ -416,9 +416,10 @@ def stacked(
         if vmax is None:
             vmax = np.max(df[label])
 
-    # automatically set alpha based on heuristic
-    if alpha is None:
-        alpha = 0.2 / (df.shape[0] / 1000)
+    # automatically set alpha based on heuristic and cap at 1.0 for small datasets
+    if alpha is None:
+        alpha = 0.2 / (df.shape[0] / 1000)
+        alpha = min(alpha, 1.0)
 
     fig = plt.figure(figsize=(width, height))