update(arc-basic): matplotlib — comprehensive quality review

plots/arc-basic/implementations/matplotlib.py

@@ -1,17 +1,17 @@
-""" pyplots.ai
+"""pyplots.ai
 arc-basic: Basic Arc Diagram
-Library: matplotlib 3.10.8 | Python 3.13.11
-Quality: 91/100 | Created: 2025-12-23
+Library: matplotlib 3.10.8 | Python 3.14.3
+Quality: /100 | Updated: 2026-02-23
 """
 
+import matplotlib.cm as cm
+import matplotlib.colors as mcolors
 import matplotlib.patches as mpatches
 import matplotlib.pyplot as plt
 import numpy as np
 
 
 # Data: Character interactions in a story chapter
-np.random.seed(42)
-
 nodes = ["Alice", "Bob", "Carol", "David", "Eve", "Frank", "Grace", "Henry", "Iris", "Jack"]
 n_nodes = len(nodes)
 
@@ -34,62 +34,86 @@
     (8, 9, 2),  # Iris-Jack
 ]
 
-# Create plot
+weights = [w for _, _, w in edges]
+weight_min, weight_max = min(weights), max(weights)
+
+# Colormap: weight mapped to blue palette (truncated to avoid near-white)
+norm = mcolors.Normalize(vmin=weight_min - 0.8, vmax=weight_max + 0.3)
+cmap = cm.Blues
+
+# Plot
 fig, ax = plt.subplots(figsize=(16, 9))
 
 # Node positions along x-axis
-x_positions = np.linspace(0.05, 0.95, n_nodes)
-y_baseline = 0.15
+x_positions = np.linspace(0.05, 0.92, n_nodes)
+y_baseline = 0.10
 
-# Draw arcs
-for start, end, weight in edges:
+# Draw arcs (lighter weights first so strong connections render on top)
+for start, end, weight in sorted(edges, key=lambda e: e[2]):
     x_start = x_positions[start]
     x_end = x_positions[end]
 
     # Arc height proportional to distance between nodes
     distance = abs(end - start)
-    height = 0.07 * distance
+    height = 0.06 * distance
 
-    # Center and width of the arc
     x_center = (x_start + x_end) / 2
     arc_width = abs(x_end - x_start)
 
-    # Arc thickness based on weight
-    linewidth = 2.0 + weight * 1.2
+    # Thickness and color both encode weight
+    linewidth = 1.5 + weight * 1.5
+    color = cmap(norm(weight))
 
-    # Semi-transparent arcs
-    alpha = 0.55
-
-    # Create arc using Arc patch
     arc = mpatches.Arc(
         (x_center, y_baseline),
         width=arc_width,
         height=height * 2,
         angle=0,
         theta1=0,
         theta2=180,
-        color="#306998",
+        color=color,
         linewidth=linewidth,
-        alpha=alpha,
+        alpha=0.75,
     )
     ax.add_patch(arc)
 
 # Draw nodes
 ax.scatter(x_positions, [y_baseline] * n_nodes, s=500, c="#FFD43B", edgecolors="#306998", linewidths=2.5, zorder=5)
 
-# Add node labels
+# Node labels
 for x, name in zip(x_positions, nodes, strict=True):
-    ax.text(x, y_baseline - 0.06, name, ha="center", va="top", fontsize=16, fontweight="bold", color="#306998")
+    ax.text(x, y_baseline - 0.045, name, ha="center", va="top", fontsize=16, fontweight="bold", color="#306998")
+
+# Weight colorbar (distinctive matplotlib feature)
+tick_norm = mcolors.Normalize(vmin=weight_min, vmax=weight_max)
+sm = cm.ScalarMappable(cmap=cmap, norm=tick_norm)
+sm.set_array([])
+cbar = fig.colorbar(sm, ax=ax, shrink=0.45, aspect=15, pad=0.02)
+cbar.set_label("Connection Strength", fontsize=16)
+cbar.set_ticks([1, 2, 3])
+cbar.ax.tick_params(labelsize=14)
+
+# Baseline indicator (thin horizontal line for visual grounding)
+ax.plot(
+    [x_positions[0] - 0.02, x_positions[-1] + 0.02],
+    [y_baseline, y_baseline],
+    color="#306998",
+    linewidth=0.8,
+    alpha=0.25,
+    zorder=1,
+)
 
 # Styling
-ax.set_xlim(-0.02, 1.02)
-ax.set_ylim(-0.05, 0.85)
-ax.set_aspect("equal")
-
-# Remove axes
+ax.set_xlim(-0.02, 0.98)
+ax.set_ylim(-0.07, 0.68)
 ax.axis("off")
 
-ax.set_title("Character Interactions · arc-basic · matplotlib · pyplots.ai", fontsize=24, pad=20)
+ax.set_title(
+    "Character Interactions \u00b7 arc-basic \u00b7 matplotlib \u00b7 pyplots.ai",
+    fontsize=24,
+    fontweight="medium",
+    pad=20,
+)
 
 plt.tight_layout()
 plt.savefig("plot.png", dpi=300, bbox_inches="tight")

plots/arc-basic/metadata/matplotlib.yaml

@@ -1,16 +1,16 @@
 library: matplotlib
 specification_id: arc-basic
 created: '2025-12-23T08:48:38Z'
-updated: '2025-12-23T09:04:24Z'
-generated_by: claude-opus-4-5-20251101
+updated: '2026-02-23T12:00:00+00:00'
+generated_by: claude-opus-4-6
 workflow_run: 20455960794
 issue: 0
-python_version: 3.13.11
+python_version: '3.14.3'
 library_version: 3.10.8
 preview_url: https://storage.googleapis.com/pyplots-images/plots/arc-basic/matplotlib/plot.png
 preview_thumb: https://storage.googleapis.com/pyplots-images/plots/arc-basic/matplotlib/plot_thumb.png
 preview_html: null
-quality_score: 91
+quality_score: null
 impl_tags:
   dependencies: []
   techniques:

plots/arc-basic/specification.md

@@ -17,6 +17,7 @@ An arc diagram arranges nodes along a single horizontal line and draws connectio
 - `edges` (list of tuples) - Pairs of node indices or names indicating connections
 - `weights` (numeric, optional) - Edge weights affecting arc thickness or height
 - Size: 10-50 nodes typical for readability
+- Example: Character interactions in a novel — nodes as characters, edges as dialogue exchanges
 
 ## Notes
 

plots/arc-basic/specification.yaml

@@ -6,7 +6,7 @@ title: Basic Arc Diagram
 
 # Specification tracking
 created: 2025-12-15T20:43:43Z
-updated: 2025-12-15T20:43:43Z
+updated: 2026-02-23T12:00:00Z
 issue: 991
 suggested: MarkusNeusinger
 
@@ -18,8 +18,10 @@ tags:
   data_type:
     - network
     - relational
+    - categorical
+    - ordinal
   domain:
     - general
   features:
     - basic
-    - connection-visualization
+    - 2d