Intraday Chart with Breaks (II)

Overview

This advanced variant handles complex intraday patterns with multiple sessions per day, irregular breaks, or different schedules across weekdays. It's designed for markets with lunch breaks, pre-market/after-hours sessions, or varying operational windows.

When to use

Markets with lunch breaks (Asian exchanges)
Pre-market and after-hours trading visualization
Different session patterns by day of week
Multiple venues with different trading hours
Complex operational schedules

Not ideal

Simple single-session scenarios (use basic intraday chart)
When all breaks can be treated uniformly
Continuous 24/7 data

Key variations

Morning and afternoon sessions with lunch break
Pre-market, regular, and after-hours sessions
Different schedules Monday-Friday
Holiday and special trading day handling
Multiple time zones on same chart

Use cases

Hong Kong Stock Exchange (morning: 9:30-12:00, afternoon: 13:00-16:00)
US extended hours (pre-market 4:00-9:30, regular 9:30-16:00, after-hours 16:00-20:00)
European markets with varying hours
Forex markets transitioning between sessions
Global commodity exchanges

Data (CSV)

datetime,price,session
2025-01-06 09:30:00,150.25,morning
2025-01-06 11:00:00,151.10,morning
2025-01-06 12:00:00,152.45,morning
2025-01-06 13:00:00,151.80,afternoon
2025-01-06 14:30:00,153.20,afternoon
2025-01-06 16:00:00,153.50,afternoon
2025-01-07 09:30:00,154.20,morning
2025-01-07 11:00:00,153.90,morning
2025-01-07 12:00:00,155.10,morning
2025-01-07 13:00:00,156.00,afternoon

Performance tips

Index data by session type for faster filtering
Pre-compute session boundaries
Use efficient date/time libraries
Consider caching for commonly viewed date ranges

FAQ

How to visualize session transitions? Use vertical divider lines or subtle background shading to mark breaks. Add session labels if space permits.

Should I show gap sizes? For predictable breaks (lunch), usually no. For variable breaks (maintenance windows), consider adding duration annotations.

How to compare across sessions? Consider small multiples (one chart per session type) or use color coding to distinguish sessions within a single chart.

Can I overlay multiple days with aligned sessions? Yes, this can reveal intraday patterns. Normalize time to show typical session behavior across many days.

How to handle partial data? If data is missing during a session, leave gaps. Don't interpolate across significant time holes without clearly marking it.

Example

Guide