scippneutron.tof.unwrap

This module provides functionality for unwrapping raw frames of neutron time-of-flight data.

The module handles standard unwrapping, unwrapping in pulse-skipping mode, and unwrapping for WFM instruments, as well as combinations of the latter two. The functions defined here are meant to be used as providers for a Sciline pipeline. See https://scipp.github.io/sciline/ on how to use Sciline.

Module Attributes

Choppers	Choppers used to define the frame parameters.
FrameAtSample	Result of passing the source pulse through the chopper cascade.
FrameAtDetector	Result of passing the source pulse through the chopper cascade to the detector.
FrameBounds	The computed frame boundaries, used to unwrap the raw timestamps.
FramePeriod	The period of a frame, a (small) integer multiple of the source period.
FrameWrappedTimeOffset	Time offsets wrapped around at the frame period.
Ltotal	Total distance between the source and the detector(s).
PulseOffset	Offset from the start of the frame in pulse-skipping mode, multiple of pulse period.
PulsePeriod	Period of the source pulses, i.e., time between consecutive pulse starts.
PulseStride	Stride of used pulses.
PulseWrappedTimeOffset	Time offsets wrapped at the pulse period, typically NXevent_data/event_time_offset.
RawData	Raw detector data loaded from a NeXus file, e.g., NXdetector containing NXevent_data.
SourceChopperName	Name of the chopper defining the source location and time-of-flight time origin.
SourceChopper	Chopper defining the source location and time-of-flight time origin.
SampleDistance	Location of the sample along the incident beam.
SourceTimeRange	Time range of the source pulse, used for computing frame bounds.
SourceWavelengthRange	Wavelength range of the source pulse, used for computing frame bounds.
SubframeBounds	The computed subframe boundaries, used to offset the raw timestamps for WFM.
TimeZero	Time of the start of the most recent pulse, typically NXevent_data/event_time_zero.
UnwrappedData	Detector data with unwrapped time offset and pulse time coordinates.
TofData	Detector data with time-of-flight and time zero coordinates.
TimeOffset	Unwrapped time offset relative to the pulse time.
DeltaFromWrapped	Positive delta to be added to the input time offsets to unwrap them.

Functions

frame_at_detector(source_wavelength_range, ...)	Return the frame at the detector.
frame_bounds(frame)	rtype: tof.unwrap.FrameBounds (scipp.DataGroup)
frame_period(pulse_period, pulse_stride)	rtype: tof.unwrap.FramePeriod (scipp.Variable)
frame_wrapped_time_offset(offset)	Without pulse-skipping, this is an identity function.
frame_wrapped_time_offset_pulse_skipping(...)	Return the time offset wrapped around at the frame period.
offset_from_wrapped(wrapped_time_offset, ...)	Offset of the input time offsets from the start of the frame emitting the neutron.
pulse_offset(pulse_period, pulse_stride, ...)	Return the offset of a pulse within a frame.
pulse_wrapped_time_offset(da)	In NXevent_data, event_time_offset is the time offset since event_time_zero, which is the start of the most recent pulse.
source_chopper(choppers, source_time_range, ...)	Return the chopper defining the source location and time-of-flight time origin.
subframe_bounds(frame)	Used for WFM.
time_of_flight_origin_from_chopper(...)	Compute the time-of-flight origin from a source chopper.
time_of_flight_origin_from_choppers_providers([wfm])	Return the providers for computing the time-of-flight origin via the chopper cascade.
time_of_flight_origin_wfm_from_chopper(...)	Compute the time-of-flight origin from a source chopper in the WFM case.
time_of_flight_providers()	Return the providers computing the time-of-flight and time-zero coordinates.
time_offset(unwrapped)	Extract the time offset coord of the unwrapped input data.
time_zero(da)	In NXevent_data, event_time_zero is the start of the most recent pulse.
to_time_of_flight(da, origin, ltotal)	Return the input data with 'tof', 'time_zero', and corrected 'Ltotal' coordinates.
unwrap_data(da, delta)	Return the input data with unwrapped time offset and pulse time.
unwrap_providers([pulse_skipping])	Return the list of providers for unwrapping frames.

Classes

TimeOfFlightOrigin(time, distance)

The origin of the time-of-flight, time since pulse time and distance from source.