libtcspc.DataLostEvent¶

class libtcspc.DataLostEvent(numeric_traits=None)[source]¶

Bases: EventType

Event indicating that the data source detected a buffer overflow.

Emitted when an upstream data source (FIFO, DMA, or similar) detected that one or more events were lost before they could be delivered. Subsequent events may therefore be missing and the abstime field may have skipped time.

Parameters:: numeric_traits (NumericTraits or None) – Set of integer types parameterising the C++ event. None (the default) uses NumericTraits defaults.

Notes

The corresponding C++ event has the field abstime. The source should continue to produce overflow notifications for subsequent occurrences; cancelling the stream in response to data loss is the responsibility of a downstream processor.

A value is constructed by giving all fields, e.g. DataLostEvent(nt).value(abstime=42); read them back as attributes (inst.abstime).

Constructing and inspecting individual event values from Python is intended for debugging and learning only and is extremely slow; production graphs process events in compiled C++ and exchange bulk data via buckets.