[indicator-bollinger] Bollinger Bands Indicator Chart

[MarkusNeusinger]

Bollinger Bands technical indicator overlaid on price chart. Shows middle band (SMA), upper band (+2 std dev), and lower band (-2 std dev). Used to identify overbought/oversold conditions and volatility in stock/crypto analysis.

[claude]

✅ Spec ID: indicator-bollinger

Rationale: Uses the indicator-* pattern consistent with indicator-macd for technical analysis charts. Bollinger Bands is a distinct volatility indicator different from the generic band-basic plot.

Add label approved to begin generation.

[github-actions]

✅ Specification Ready: indicator-bollinger

PR: #3239

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specification.md

indicator-bollinger: Bollinger Bands Indicator Chart

Description

A Bollinger Bands chart displays price data with a volatility envelope consisting of three lines: a middle band (simple moving average), an upper band (SMA plus 2 standard deviations), and a lower band (SMA minus 2 standard deviations). This technical indicator helps traders identify overbought/oversold conditions, volatility patterns, and potential price breakouts by showing how prices relate to their recent statistical range.

Applications

• Identifying overbought conditions when price touches the upper band in stock trading
• Detecting oversold opportunities when price approaches the lower band in cryptocurrency analysis
• Measuring market volatility by observing band width expansion and contraction
• Spotting potential trend reversals when prices break outside the bands

Data

• date (datetime) - Trading date or timestamp for each period
• close (numeric) - Closing price for each period
• sma (numeric) - Simple moving average (middle band), typically 20-period
• upper_band (numeric) - Upper band value (SMA + 2 standard deviations)
• lower_band (numeric) - Lower band value (SMA - 2 standard deviations)
• Size: 60-200 periods for meaningful pattern visualization
• Example: Daily stock prices with 20-day SMA and 2 standard deviation bands over 120 trading days

Notes

• Display the price line (close) prominently, typically as a line or candlestick
• Upper and lower bands should use the same color with semi-transparent fill between them
• Middle band (SMA) should be clearly visible, often as a dashed or dotted line
• Standard parameters are 20-period SMA with 2 standard deviations, note in chart if different
• Consider showing band width as a secondary indicator or noting squeeze patterns

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Next: Add approved label to merge this specification to main.

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🤖 spec-create workflow

[github-actions]

🚀 Specification Merged!

Specification: indicator-bollinger
PR: #3239 (merged)

The specification is now in main and synced to PostgreSQL.

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Next: Add generate:{library} labels to start generating implementations.

Available libraries: matplotlib, seaborn, plotly, bokeh, altair, plotnine, pygal, highcharts, letsplot

Or use workflow dispatch for bulk operations.

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🤖 spec-create workflow