SpectralWindow¶

class SpectralWindow(spw_id: int, name: str, spw_type: str, bandwidth: float, ref_freq: dict, mean_freq: float, chan_freqs: ndarray, chan_widths: ndarray, chan_effective_bws: ndarray, sideband: int, baseband: int, receiver: str | None, freq_lo: list[float] | ndarray | None, band: str = 'Unknown', spectralspec: str | None = None, transitions: list[str] | None = None, sdm_num_bin: int | None = None, correlation_bits: str | None = None, median_receptor_angle: ndarray | None = None, specline_window: bool = False, grouping_id: str | None = None)[source]¶

Bases: object

A logical representation of a spectral window (spw).

id¶: The numerical identifier of this spectral window within the SPECTRAL_WINDOW subtable of the MeasurementSet.

band¶: Frequency band.

bandwidth¶: The total bandwidth.

baseband¶: The baseband.

channels¶: Frequency information of each channel in spectral window, i.e., frequencies, channel width, effective bandwidth.

freq_lo¶: A list of LO frequencies.

intents¶: the observing intents that have been observed using this spectral window.

mean_frequency¶: Mean frequency of spectral window.

name¶: Spectral window name.

receiver¶: Receiver type, e.g., 'TSB'.

ref_frequency¶: The reference frequency.

sideband¶: Side band.

transitions¶: Spectral transitions recorded associated with spectral window.

type¶: Spectral window type, e.g., 'TDM'.

sdm_num_bin¶: Number of bins for online spectral averaging.

correlation_bits¶: Number of bits used for correlation.

median_receptor_angle¶: Median feed receptor angle.

specline_window¶: Whether spw is intended for spectral line or continuum (VLA only).

grouping_id¶: Grouping ID to uniquely identify this spw in different MOUS within the same GOUS (ALMA-only, introduced in Cycle 12).

Attributes Summary

`band`
`bandwidth`
`baseband`
`centre_frequency`	Return the center frequency of the SpectralWindow.
`channels`
`correlation_bits`
`frame`	Return the reference frame code of the SpectralWindow.
`freq_lo`
`grouping_id`
`id`
`intents`
`max_frequency`	Return the maximum frequency of the SpectralWindow.
`mean_frequency`
`median_receptor_angle`
`min_frequency`	Return the minimum frequency of the SpectralWindow.
`name`
`num_channels`	Return the number of channels in the SpectralWindow.
`receiver`
`ref_frequency`
`sdm_num_bin`
`sideband`
`specline_window`
`spectralspec`
`transitions`
`type`

Methods Summary

channel_range(minfreq, maxfreq)

Return the channel range for given minimum/maximum frequency.

Attributes Documentation

band¶

bandwidth¶

baseband¶

centre_frequency¶: Return the center frequency of the SpectralWindow.

channels¶

correlation_bits¶

frame¶: Return the reference frame code of the SpectralWindow.

freq_lo¶

grouping_id¶

id¶

intents¶

max_frequency¶: Return the maximum frequency of the SpectralWindow.

mean_frequency¶

median_receptor_angle¶

min_frequency¶: Return the minimum frequency of the SpectralWindow.

name¶

num_channels¶: Return the number of channels in the SpectralWindow.

receiver¶

ref_frequency¶

sdm_num_bin¶

sideband¶

specline_window¶

spectralspec¶

transitions¶

type¶

Methods Documentation

channel_range(minfreq: Frequency, maxfreq: Frequency) → tuple[int, int] | tuple[None, None][source]¶

Return the channel range for given minimum/maximum frequency.

Parameters:

minfreq -- Minimum frequency as measures.Frequency object.
maxfreq -- Maximum frequency as measures.Frequency object.

Returns:

2-Tuple of integers representing indices (min, max) of channel range end-points corresponding to given min/max frequency.