setigen.funcs package

setigen.funcs.f_profiles module

Sample spectral profiles for signal injection.

For any given time sample, these functions map out the intensity in the frequency direction (centered at a particular frequency).

setigen.funcs.f_profiles.box_f_profile(width)[source]

Square intensity profile in the frequency direction.

Parameters:

width (float or astropy.Quantity) – Width of signal

Returns:

f_profile

Return type:

func

setigen.funcs.f_profiles.gaussian_f_profile(width)[source]

Gaussian profile.

Parameters:

width (float or astropy.Quantity) – FWHM of Gaussian profile

Returns:

f_profile

Return type:

func

setigen.funcs.f_profiles.multiple_gaussian_f_profile(width)[source]

Example adding multiple Gaussians in the frequency direction.

Parameters:

width (float or astropy.Quantity) – FWHM of Gaussian profile

Returns:

f_profile

Return type:

func

setigen.funcs.f_profiles.lorentzian_f_profile(width)[source]

Lorentzian profile.

Parameters:

width (float or astropy.Quantity) – FWHM of Lorentzian profile

Returns:

f_profile

Return type:

func

setigen.funcs.f_profiles.voigt_f_profile(g_width, l_width)[source]

Voigt profile.

Further information here: https://en.wikipedia.org/wiki/Voigt_profile.

Parameters:

  • g_width (float or astropy.Quantity) – FWHM of Gaussian profile

  • l_width (float or astropy.Quantity) – FWHM of Lorentzian profile

Returns:

f_profile

Return type:

func

setigen.funcs.f_profiles.sinc2_f_profile(width, width_mode='fwhm', trunc=True)[source]

Sinc squared profile; width is the FWHM of the squared normalized sinc function.

The trunc parameter controls whether or not the sinc squared profile is truncated at the first root (e.g. zeroed out for more distant frequencies).

Note that you can model an ideal cosine signal by using width=2*frame.df, width_mode="crossing", and trunc=False.

Parameters:

  • width (float or astropy.Quantity) – Signal width, in Hz

  • width_mode ({"fwhm", "crossing"}, default: "fwhm") – How to interpret width. Can be “fwhm” or “crossing”, for zero crossing.

  • trunc (bool, default: True) – Whether to truncate signal after first zero crossing

Returns:

f_profile

Return type:

func

setigen.funcs.paths module

Sample signal paths for signal injection.

For any given starting frequency, these functions map out the path of a signal as a function of time in time-frequency space.

setigen.funcs.paths.constant_path(f_start, drift_rate)[source]

Constant drift rate.

Parameters:

  • f_start (float or astropy.Quantity) – Starting center frequency

  • drift_rate (float or astropy.Quantity) – Doppler drift rate

Returns:

path

Return type:

func

setigen.funcs.paths.squared_path(f_start, drift_rate)[source]

Quadratic signal path; drift_rate here only refers to the starting slope.

Parameters:

  • f_start (float or astropy.Quantity) – Starting center frequency

  • drift_rate (float or astropy.Quantity) – Doppler drift rate

Returns:

path

Return type:

func

setigen.funcs.paths.sine_path(f_start, drift_rate, period, amplitude)[source]

Sine path in time-frequency space.

Parameters:

  • f_start (float or astropy.Quantity) – Starting center frequency

  • drift_rate (float or astropy.Quantity) – Doppler drift rate

  • period (float or astropy.Quantity) – Modulation period

  • amplitude (float or astropy.Quantity) – Modulation amplitude

Returns:

path

Return type:

func

setigen.funcs.paths.simple_rfi_path(f_start, drift_rate, spread, spread_type='uniform', rfi_type='stationary', seed=None)[source]

A crude simulation of one style of RFI that shows up, in which the signal jumps around in frequency. This method samples the center frequency for each time sample from either a uniform or normal distribution.

Parameters:

  • f_start (float or astropy.Quantity) – Starting center frequency

  • drift_rate (float or astropy.Quantity) – Doppler drift rate

  • spread (float or astropy.Quantity) – Range of center frequency variations

  • spread_type ({"uniform", "normal"}, default: "uniform") – Type of frequency variation

  • rfi_type ({"stationary", "random_walk"}, default: "stationary") – The “stationary” option only offsets with respect to a straight-line path, but “random_walk” accumulates frequency offsets over time.

  • seed (None, int, Generator, optional) – Random seed or seed generator

Returns:

path

Return type:

func

setigen.funcs.t_profiles module

Sample intensity profiles for signal injection.

These functions calculate the signal intensity and variation in the time direction.

setigen.funcs.t_profiles.constant_t_profile(level=1)[source]

Constant intensity profile.

Parameters:

level (float, default: 1) – Intensity level

Returns:

t_profile

Return type:

func

setigen.funcs.t_profiles.sine_t_profile(period, phase=0, amplitude=1, level=1)[source]

Intensity varying as a sine curve.

Parameters:

  • period (float or astropy.Quantity) – Modulation period

  • phase (float, default: 0) – Modulation phase

  • amplitude (float, default: 1) – Modulation amplitude

  • level (float, default: 1) – Mean intensity level

Returns:

t_profile

Return type:

func

setigen.funcs.t_profiles.periodic_gaussian_t_profile(pulse_width, period, phase=0, pulse_offset_width=0, pulse_direction='rand', pnum=3, amplitude=1, level=1, min_level=0, seed=None)[source]

Intensity varying as Gaussian pulses, allowing for variation in the arrival time of each pulse.

Parameters:

  • pulse_width (float or astropy.Quantity) – FWHM width of individual pulses

  • period (float or astropy.Quantity) – Baseline modulation period

  • phase (float or astropy.Quantity, default: 0) – Baseline modulation phase

  • pulse_offset_width (float or astropy.Quantity, default: 0) – FWHM of timing variation from the modulation period

  • pulse_direction ({"rand", "up", "down"}, default: "rand") – Whether the intensity increases or decreases from the baseline level

  • pnum (float or astropy.Quantity, default: 3) – Number of Gaussians pulses to consider when calculating the intensity at each timestep. The higher this number, the more accurate the intensities.

  • amplitude (float, default: 1) – Pulse magnitude

  • level (float, default: 1) – Baseline intensity level

  • min_level (float, default: 0) – Minimum intensity level

  • seed (None, int, Generator, optional) – Random seed or seed generator

Returns:

t_profile

Return type:

func

setigen.funcs.bp_profiles module

setigen.funcs.bp_profiles.constant_bp_profile(level=1)[source]

Constant bandpass profile.

setigen.funcs.func_utils module

setigen.funcs.func_utils.gaussian(x, x0, sigma)[source]

Basic Gaussian function centered at x0.

setigen.funcs.func_utils.lorentzian(x, x0, gamma)[source]

Basic Lorentzian function centered at x0.

setigen.funcs.func_utils.voigt(x, x0, sigma, gamma)[source]

Basic Voigt profile centered at x0.

setigen.funcs.func_utils.voigt_fwhm(g_width, l_width)[source]

Accurate to 0.0003% for a pure Lorentzian profile, precise for a pure Gaussian.

Source: https://en.wikipedia.org/wiki/Voigt_profile.