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ShiftedWindows

Extract overlapped windows from the given time series.

Note that this node is currently only usable in offline mode. In the output the time axis is replaced by two axes, an instance axis called timewindow which indicates the average time of the window and the time axis which indicates the relative time in the window with the reference to the middle time-point. If remove_gaps is True, all windows which overlap gaps in the time-sequence will be removed. Version 1.0.0

Ports/Properties

data

Data to process.

  • verbose name: Data
  • default value: None
  • port type: DataPort
  • value type: Packet (can be None)
  • data direction: INOUT

win_len

Sliding window length. A longer window will yield a better estimate, but the spectrum will change more slowly and will also react more slowly to changes. Typical settings for EEG phenomena are 0.5 to 5 seconds, but for very slowly (or rapidly) changing brain dynamics, longer (or shorter) windows may be used.

  • verbose name: Sliding Window Length
  • default value: 2
  • port type: FloatPort
  • value type: float (can be None)

offset_len

Amount of shift or offset between the beginning of the time window segments. If this value is not set, it is assumed that the overlap length is half of the window length, corresponding to 50% overlap.

  • verbose name: Offset Length
  • default value: None
  • port type: FloatPort
  • value type: float (can be None)

unit

Unit in which the window and offset length is given.

  • verbose name: Unit Of Measurement For Window Length
  • default value: seconds
  • port type: EnumPort
  • value type: str (can be None)

remove_gaps

Remove all windows which overlap gaps in the data.

  • verbose name: Remove Gaps
  • default value: True
  • port type: BoolPort
  • value type: bool (can be None)

max_gap_length

Maximum length of time-stamp gaps that are allowed in segments. If a gap between successive samples is larger than this duration in seconds, then the affected segment is not extracted. Optional. Note that if your time stamps are jittered, this will generate a lot of false positives unless you use a very generous cutoff. You can use the DejitterTimestamps node early during your processing to fix that.

  • verbose name: Max Gap Length
  • default value: 0.2
  • port type: FloatPort
  • value type: float (can be None)

timestamp_origin

The origin of the timestamp for each window, sourced from the original timestamps for that window. mean: Take the average time within each window first: Take the first time within each window.

  • verbose name: Timestamp Origin
  • default value: mean
  • port type: EnumPort
  • value type: str (can be None)

create_axis

Type of axis to create to index the windows. The axis will by default carry the custom label "timewindow", unless the axis has a label defined in the axis definition string, as in time.mylabel.

  • verbose name: Create Axis
  • default value: instance
  • port type: ComboPort
  • value type: str (can be None)

set_breakpoint

Set a breakpoint on this node. If this is enabled, your debugger (if one is attached) will trigger a breakpoint.

  • verbose name: Set Breakpoint (Debug Only)
  • default value: False
  • port type: BoolPort
  • value type: bool (can be None)

metadata

User-definable meta-data associated with the node. Usually reserved for technical purposes.

  • verbose name: Metadata
  • default value: {}
  • port type: DictPort
  • value type: dict (can be None)