[bar-basic] bokeh implementation

[github-actions]

[bar-basic] bokeh Implementation

Parent Issue: #202
Spec: specs/bar-basic.md
Library: bokeh
Feature Branch: plot/bar-basic

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Attempt History

Attempts will be documented below as comments.

[github-actions]

Attempt 1/3

Technical Approach

• Imports: import pandas as pd, from bokeh.io import export_png, from bokeh.models import ColumnDataSource
• Config: color=#306998

Status

• PR: feat(bokeh): implement bar-basic #305
• File: plots/bokeh/vbar/bar-basic/default.py
• Workflow: 19995638443

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[github-actions]

🧪 Test Results (PR #305)

Python:

📊 Plot Preview (Python 3.13)

bokeh (default) - UPDATE

Before	After

View version history (4 versions)

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🤖 Generated by gen-preview workflow

[claude]

AI Review - Attempt 1/3

Quality Evaluation

Evaluator	Score	Verdict
Claude	88/100	approve

Criteria Checklist

• VQ-001: Axes labeled correctly - X-axis "Category", Y-axis "Value"
• VQ-002: Visual clarity - Grid subtle (y-grid only, alpha=0.3)
• VQ-003: Elements clear - Bars visible with good contrast (steelblue, alpha=0.8)
• VQ-004: No overlap - Labels and ticks don't overlap
• VQ-005: Legend present - N/A (single series, not required)
• VQ-006: Colorblind safe - Steelblue is safe color
• VQ-007: Image size - Default 1600x900, not 4800x2700 (minor)
• VQ-008: Title - Present "Basic Bar Chart", centered
• CQ-001: Type hints present - Full type annotations
• CQ-002: Docstring - Complete Google-style with Args, Returns, Raises, Example
• CQ-003: Input validation - Checks empty data and missing columns
• CQ-004: Clear error messages - Shows available columns on KeyError
• CQ-005: No magic numbers - Bar width, alpha, colors all parameterized
• CR-001: Data accurate - Correct columns used for categories and values
• CR-002: Spec compliance - All required features implemented
• CR-003: Edge cases - Empty data raises ValueError, NaN values dropped gracefully

Issues Found

1. VQ-007 PARTIAL: Default figsize is (1600, 900) instead of recommended (4800, 2700). However, it is configurable via parameter.

Positive Highlights

• Excellent use of ColumnDataSource per bokeh.md guidelines
• Correct folder placement (vbar/) per library rules
• Comprehensive input validation with helpful error messages
• Well-documented with complete docstring
• Proper categorical x-axis setup with x_range=categories
• Y-axis correctly starts at 0
• Clean styling with subtle grid (x-grid disabled, y-grid at 0.3 alpha)
• Rotation parameter for x-axis labels (useful for long category names)

AI Feedback for Next Attempt

Consider updating default figsize to (4800, 2700) per style guide, though current implementation is acceptable as size is configurable.

Verdict: APPROVED

Score: 88/100 (Good - meets all critical criteria, one minor deviation on default figure size)