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clean

Functions

clean(data, lowcut=0.5, highcut=4, sample_rate=1000, order=3, axis=-1, forward_backward=True)

Clean PPG signal using biquad filter.

By default applies a 3rd order Butterworth filter between 0.5 and 4 Hz.

Parameters:

  • data (NDArray) –

    Signal

  • lowcut (float, default: 0.5 ) –

    Lower cutoff in Hz. Defaults to 0.5 Hz.

  • highcut (float, default: 4 ) –

    Upper cutoff in Hz. Defaults to 4 Hz.

  • sample_rate (float, default: 1000 ) –

    Sample rate in Hz. Defaults to 1000 Hz.

  • order (int, default: 3 ) –

    Filter order. Defaults to 3 (3rd order Butterworth filter).

  • axis (int, default: -1 ) –

    Axis to apply against. Defaults to -1.

  • forward_backward (bool, default: True ) –

    Apply filter forward and backward. Defaults to True.

Returns:

  • NDArray –

    npt.NDArray: Cleaned signal

Source code in physiokit/ppg/clean.py 
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def clean(
    data: npt.NDArray,
    lowcut: float = 0.5,
    highcut: float = 4,
    sample_rate: float = 1000,
    order: int = 3,
    axis: int = -1,
    forward_backward: bool = True,
) -> npt.NDArray:
    """Clean PPG signal using biquad filter.

    By default applies a 3rd order Butterworth filter between 0.5 and 4 Hz.

    Args:
        data (npt.NDArray): Signal
        lowcut (float, optional): Lower cutoff in Hz. Defaults to 0.5 Hz.
        highcut (float, optional): Upper cutoff in Hz. Defaults to 4 Hz.
        sample_rate (float, optional): Sample rate in Hz. Defaults to 1000 Hz.
        order (int, optional): Filter order. Defaults to 3 (3rd order Butterworth filter).
        axis (int, optional): Axis to apply against. Defaults to -1.
        forward_backward (bool, optional): Apply filter forward and backward. Defaults to True.

    Returns:
        npt.NDArray: Cleaned signal
    """

    return filter_signal(
        data=data,
        lowcut=lowcut,
        highcut=highcut,
        sample_rate=sample_rate,
        order=order,
        axis=axis,
        forward_backward=forward_backward,
    )