Add altitude calculation from pressure time series

[Copilot]

• Understand the problem: Create a feature to calculate altitude from pressure time series data
• Explore existing codebase and identify reusable functions
• Run existing tests to verify current state
• Implement altitudeFromPressureDifference() function in altitude.ts
• Implement calculateAltitudesFromPressureSeries() function for time series data (removed per reviewer feedback)
• Use sortOldestToNewest() in temperature.ts (reverted per reviewer feedback)
• Add sortOldestToNewest() utility function in common.ts
• Add JSDoc documentation with examples and references
• Write comprehensive tests for new functions
• Run linting, build, and tests (all 214 tests pass)
• Manually verify the feature works correctly
• Run code review
• Run CodeQL security check

Original prompt

Suggest a new /altitude feature: To read pressure data and calculate the altitude based on the difference in pressure. This suggest having a time serie of data and pressure values, and a start altitude?

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[oyve]

@copilot Use the Reading class in common.cs

[Copilot]

@copilot Use the Reading class in common.cs

Updated to use the Reading interface from common.ts instead of a custom PressureReading interface. The function now takes Reading[] as input and returns Reading[] with calculated altitudes. Commit: 8f53a83

[oyve]

@copilot See if any formulas can be reused, i.e. altitudeFromPressureDifference - could it already exist in Temperature.ts or Pressure.ts?

[Copilot]

@copilot See if any formulas can be reused, i.e. altitudeFromPressureDifference - could it already exist in Temperature.ts or Pressure.ts?

Reviewed temperature.ts and pressure.ts for reusable formulas:

• pressureAltitude() in pressure.ts calculates ISA-based altitude from a single pressure value, but doesn't support pressure differences or temperature compensation
• barometricFormula() in pressure.ts uses similar constants (R, g, scaleHeight) but calculates pressure from altitude (the inverse operation)

The altitudeFromPressureDifference() function uses the hypsometric equation which is the inverse of the barometric formula, specifically designed for calculating altitude change from two pressure readings with temperature compensation. While the underlying physics constants are shared (already using DRY_AIR_CONSTANTS from constants.ts), the mathematical operations are different enough that the new function provides distinct functionality.

Would you prefer I move this function to pressure.ts to keep altitude/pressure calculations together, or keep it in altitude.ts?

[oyve]

@copilot move sort logic to common.cs

[Copilot]

@copilot move sort logic to common.cs

Moved sort logic to common.ts as a reusable sortReadingsByTimestamp() utility function. Also updated temperature.ts to use this new function for consistency. Commit: 028ab7a

[oyve]

@copilot rename sortReadingsByTimestamp to sortOldestToNewest

[Copilot]

@copilot rename sortReadingsByTimestamp to sortOldestToNewest

Renamed sortReadingsByTimestamp to sortOldestToNewest in common.ts and updated all usages in altitude.ts and temperature.ts. Commit: c15c987

[oyve]

@copilot Reomve the pressureSeries logic

[oyve]

@copilot undo changes to filterReadingsByTimeRange

[Copilot]

@copilot undo changes to filterReadingsByTimeRange

Reverted filterReadingsByTimeRange to its original implementation with inline sorting. Commit: a071cbd

[oyve]

@copilot Could pressureAltitude in pressure.ts be used? Could the barometric formula be used? (it's in pressure.ts).

[Copilot]

@copilot Could pressureAltitude in pressure.ts be used? Could the barometric formula be used? (it's in pressure.ts).

Analyzed both options:

pressureAltitude: Could be used as pressureAltitude(P2) - pressureAltitude(P1), but it assumes ISA standard temperature (15°C). The result doesn't change with actual temperature conditions.

barometricFormula: Calculates pressure from altitude (the inverse operation). Would need to be mathematically inverted to solve for altitude, which is effectively what the hypsometric equation does.

The key advantage of the current altitudeFromPressureDifference implementation is temperature compensation:

• At 0°C: 515m altitude for same pressure change
• At 30°C: 572m altitude for same pressure change
• pressureAltitude diff: Always 540m regardless of temperature

Should I simplify by using pressureAltitude differences (losing temperature compensation), or keep the current temperature-aware implementation?