update(area-basic): altair — comprehensive quality review

Added traffic spike, interactive tooltips, cleaner axis config

Author: MarkusNeusinger

plots/area-basic/implementations/altair.py

@@ -1,7 +1,7 @@
-""" pyplots.ai
+"""pyplots.ai
 area-basic: Basic Area Chart
-Library: altair 6.0.0 | Python 3.13.11
-Quality: 91/100 | Created: 2025-12-23
+Library: altair 6.0.0 | Python 3.14.2
+Quality: /100 | Updated: 2026-02-11
 """
 
 import altair as alt
@@ -18,6 +18,8 @@
 weekly_pattern = np.array([1.2, 1.1, 1.0, 1.05, 1.15, 0.8, 0.7] * 5)[:30]
 noise = np.random.randn(30) * 300
 visitors = (base + trend) * weekly_pattern + noise
+# Add a traffic spike mid-month (e.g., marketing campaign on Jan 15)
+visitors[14] *= 1.4
 visitors = np.maximum(visitors, 1000).astype(int)
 
 df = pd.DataFrame({"date": dates, "visitors": visitors})
@@ -27,20 +29,19 @@
     alt.Chart(df)
     .mark_area(opacity=0.4, color="#306998", line={"color": "#306998", "strokeWidth": 3})
     .encode(
-        x=alt.X("date:T", title="Date", axis=alt.Axis(labelFontSize=18, titleFontSize=22)),
-        y=alt.Y(
-            "visitors:Q",
-            title="Daily Visitors",
-            scale=alt.Scale(domain=[0, df["visitors"].max() * 1.1]),
-            axis=alt.Axis(labelFontSize=18, titleFontSize=22),
-        ),
+        x=alt.X("date:T", title="Date"),
+        y=alt.Y("visitors:Q", title="Daily Visitors (count)", scale=alt.Scale(domain=[0, df["visitors"].max() * 1.1])),
+        tooltip=[
+            alt.Tooltip("date:T", title="Date", format="%b %d, %Y"),
+            alt.Tooltip("visitors:Q", title="Visitors", format=","),
+        ],
     )
     .properties(width=1600, height=900, title=alt.Title("area-basic · altair · pyplots.ai", fontSize=28))
-    .configure_axis(grid=True, gridOpacity=0.3, gridDash=[4, 4])
+    .configure_axis(grid=True, gridOpacity=0.3, gridDash=[4, 4], labelFontSize=18, titleFontSize=22)
     .configure_view(strokeWidth=0)
 )
 
-# Save as PNG (1600 × 900 × 3 = 4800 × 2700 px)
+# Save as PNG (1600 × 900 at scale_factor=3 → 4800 × 2700 px)
 chart.save("plot.png", scale_factor=3.0)
 
 # Save interactive HTML version

plots/area-basic/metadata/altair.yaml

@@ -1,16 +1,16 @@
 library: altair
 specification_id: area-basic
 created: '2025-12-23T00:47:41Z'
-updated: '2025-12-23T01:21:39Z'
-generated_by: claude-opus-4-5-20251101
+updated: '2026-02-11T22:20:05+00:00'
+generated_by: claude-opus-4-6
 workflow_run: 20447969752
 issue: 0
-python_version: 3.13.11
+python_version: 3.14.2
 library_version: 6.0.0
 preview_url: https://storage.googleapis.com/pyplots-images/plots/area-basic/altair/plot.png
 preview_thumb: https://storage.googleapis.com/pyplots-images/plots/area-basic/altair/plot_thumb.png
 preview_html: https://storage.googleapis.com/pyplots-images/plots/area-basic/altair/plot.html
-quality_score: 91
+quality_score: null
 impl_tags:
   dependencies: []
   techniques: []