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Step Frequency modulation

timecave.data_generation.frequency_modulation.FrequencyModulationWithStep(freq_init, t_split)

Bases: BaseFrequency

Frequency modulation with step.

This class implements frequency modulation with a step change.

Parameters:

Name Type Description Default
freq_init float or int

The initial frequency value.

 required
t_split int

The timestep at which the frequency changes.

 required

Methods:

Name Description
modulate

Adjusts the frequency based on the given time.

Raises:

Type Description
TypeError

If 'freq_init' is not a float or int. If 't_split' is not an int.
ValueError

If 'freq_init' is not greater than zero. If 't_split' is not greater than zero.
Source code in timecave/data_generation/frequency_modulation.py 
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def __init__(self, freq_init: float or int, t_split: float or int):
    self._check_freq_init(freq_init)
    self._check_t_split(t_split)

    super().__init__()
    self._freq_init = freq_init
    self._t_split = t_split

modulate(time)

Adjusts the frequency based on the given time.

This method calculates the frequency modulation based on the given time and the initial frequency value.

Parameters:

Name Type Description Default
time int

Number of timesteps for which modulation is meant to be performed.

 required

Returns:

Type Description
array

Each entry of the array corresponds to the frequency at a given timestep.

Examples:

>>> from timecave.data_generation.frequency_modulation import FrequencyModulationWithStep
>>> mod = FrequencyModulationWithStep(1, 50);
>>> mod.modulate(25)
array(1)
>>> mod.modulate(100)
array(2)
>>> mod.modulate(50)
array(1)
Source code in timecave/data_generation/frequency_modulation.py 
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def modulate(self, time: int) -> np.array:
    """
    Adjusts the frequency based on the given time.

    This method calculates the frequency modulation based on the given time
    and the initial frequency value.

    Parameters
    ----------
    time : int
        Number of timesteps for which modulation is meant to be performed.

    Returns
    ----------
    np.array
        Each entry of the array corresponds to the frequency at a given timestep.

    Examples
    --------
    >>> from timecave.data_generation.frequency_modulation import FrequencyModulationWithStep
    >>> mod = FrequencyModulationWithStep(1, 50);
    >>> mod.modulate(25)
    array(1)
    >>> mod.modulate(100)
    array(2)
    >>> mod.modulate(50)
    array(1)
    """
    initial_period = 1 / self._freq_init
    t_split_adjusted = (self._t_split // initial_period) * initial_period
    return np.where(time > t_split_adjusted, self._freq_init * 2, self._freq_init)