API Reference: Event Detection

API Reference: Event Detection

The EventDetection library groups threshold violations into discrete events with statistics and provides a viewer UI.

EventDetector

Core detector that groups consecutive threshold violations into events.

Constructor

det = EventDetector();
det = EventDetector('MinDuration', 0.5, 'MaxCallsPerEvent', 3);

Properties

Property	Type	Default	Description
MinDuration	number	0	Debounce: events shorter than this (seconds) are discarded
OnEventStart	function handle	[]	Callback invoked as f(event) when event starts
MaxCallsPerEvent	number	1	Max callback invocations per event

Methods

events = det.detect(t, values, thresholdValue, direction, label, sensorName);

Returns an array of Event objects.

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Event

Value class holding event metadata and statistics.

Properties (all read-only)

Property	Type	Description
StartTime	number	First violation timestamp
EndTime	number	Last violation timestamp
Duration	number	EndTime - StartTime
SensorName	string	Sensor/channel name
ThresholdLabel	string	e.g., "warning high"
ThresholdValue	number	Threshold that was violated
Direction	string	"high" or "low"
PeakValue	number	Worst violation (furthest from threshold)
NumPoints	number	Data points in event window
MinValue	number	Minimum value over event window
MaxValue	number	Maximum value over event window
MeanValue	number	Mean value over event window
RmsValue	number	RMS value over event window
StdValue	number	Standard deviation over event window

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EventConfig

Configuration container for the event detection system.

Properties

Property	Type	Description
Sensors	cell array	Sensor objects to analyze
SensorData	struct array	Fields: name, t, y (for click-to-plot)
MinDuration	number	Debounce filter
MaxCallsPerEvent	number	Callback limit
OnEventStart	function handle	Callback
ThresholdColors	containers.Map	Maps threshold labels to RGB colors
AutoOpenViewer	logical	Auto-open EventViewer after detection

Methods

Method	Description
det = cfg.buildDetector()	Create configured EventDetector
events = cfg.runDetection()	Detect across all sensors
cfg.addSensor(sensor, t, y)	Register sensor with data
cfg.setColor(label, [r g b])	Set color for threshold label

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EventViewer

Figure UI with Gantt-style timeline and event table with click-to-plot.

Constructor

viewer = EventViewer(events);
viewer = EventViewer(events, sensorData);
viewer = EventViewer(events, sensorData, thresholdColors);

Methods

viewer.update(newEvents);  % Refresh with new events (live mode)

UI Features

• Top panel: Gantt-style timeline — one row per sensor, colored bars per event
• Bottom panel: Table with columns: Start, End, Duration, Sensor, Threshold, Direction, Peak, NumPts, Min, Max, Mean, RMS, Std
• Dropdown filters: Filter by sensor name or threshold label
• Click-to-plot: Click a table row to open a FastPlot zoomed to that event's time range

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Convenience Functions

detectEventsFromSensor

events = detectEventsFromSensor(sensor);
events = detectEventsFromSensor(sensor, detector);

Bridges the SensorThreshold and EventDetection libraries. Resolves thresholds, detects violations, returns Event array.

printEventSummary

printEventSummary(events);

Prints a formatted event table to the console.

eventLogger

det = EventDetector('OnEventStart', eventLogger());

Returns a callback function for live console logging of events as they are detected.

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Complete Example

% Create sensor with thresholds
s = Sensor('pressure', 'Name', 'Chamber Pressure');
s.X = linspace(0, 100, 1e6);
s.Y = randn(1, 1e6) * 10 + 50;

sc = StateChannel('machine');
sc.X = [0 30 60 80];
sc.Y = [0 1 2 1];
s.addStateChannel(sc);

s.addThresholdRule(struct('machine', 1), 70, 'Direction', 'upper', 'Label', 'Run HI');
s.resolve();

% Detect events
det = EventDetector('MinDuration', 0.5);
events = detectEventsFromSensor(s, det);

% Console output
printEventSummary(events);

% Open viewer with click-to-plot
sensorData = struct('name', 'pressure', 't', s.X, 'y', s.Y);
viewer = EventViewer(events, sensorData);