LineData — Extended spectral line metadata.

This module defines the LineData class.

class admit.util.LineData.LineData(**keyval)

Class for holding information on a specific spectral line, expanding on that of the Line base class.

Parameters:

keyval : dict

Dictionary of keyword:value pairs.

Attributes

name	(str) Name of the molecule/atom. Default: “”.
uid	(str) Unique identifier for the transition. Default: “”.
formula	(str) The chemical formula. Default: “”.
transition	(str) The transition/quantum number information. Default: “”.
energies	(2 element list) List of the lower and upper state energies of the transition. Default: [0.0, 0.0].
energyunits	(str) Units of the upper/lower state energy. Default: K.
linestrength	(float) The line strength of the transition. Default: 0.0.
lsunits	(str) The units of the line strength. Default: “Debye^2”.
frequency	(float) The frequency of the transition. Default: 0.0.
funits	(str) The units of the frequency. Default: “GHz”.
blend	(int) If this molecule is blended with others. Value of 0 means no blending any other value gives the index of the blend. Default: 0 (no blending).
mass	(int) Rough mass of the molecule (H=1, C=12, etc.). Default: 0.
plain	(str) A human redable version of the chemical formula. Default: “”.
isocount	(int) A count of the number of non-standard isotopes in the molecule. For example the standard for carbon is 12C and 13C would be the non-standard isotope. Default: 0.
chans	(two element list) List of the starting and ending channels of the line. Default: [0, 0].
freqs	(two element list) List of the starting and ending frequencies of the line. Default: [0.0, 0.0].
peakintensity	(float) The peak intensity of the line in units from the input data. Default: 0.0.
peakrms	(float) The S/N of the peak of the line. Default: 0.0.
fwhm	(float) Full width half maximum of the line. Default: 0.0.
noise	(float) The rms noise of the spectrum. Default: 0.0.
hfnum	(int) Hyperfine identifier from the Tier1 database. Default: 0 (no hyperfines).
peakoffset	(float) The offset of the peak of the line from the vlsr. Default: 0.0.
velocity	(float) The velocity of the line (offset + vlsr). Default: 0.0.
force	(bool) If True then the user forced the identification via the force keyword in LineID, if False then the id was generated by LineID. Default: False.

Methods

converttoline()	Method to convert the contents of the LineData object to a Line Object
getend()	Method to get the ending channel number.
getfend()	Method to get the ending frequency.
getfstart()	Method to get the starting frequency.
getkey(key)	Method to get a data member by name
getlowerenergy()	Method to get the lower state energy.
getstart()	Method to get the starting channel number.
getupperenergy()	Method to get the upper state energy.
isequal(line)	Experimental method to compare 2 line classes
setchans(chans)	Method to set the channel range for the line.
setend(chan)	Method to set the ending channel number.
setfend(freq)	Method to set the ending frequency.
setfreqs(freqs)	Method to set the frequency range for the line.
setfstart(freq)	Method to set the starting frequency.
setkey([name, value])	Method to set the key-value pairs for the class.
setlowerenergy(value)	Method to set the lower state energy.
setstart(chan)	Method to set the starting channel number.
setupperenergy(value)	Method to set the upper state energy.

converttoline()

Method to convert the contents of the LineData object to a Line Object

Parameters:None Returns:Line object populated with the relevant data from this LineData object

getend()

Method to get the ending channel number.

Parameters:None Returns:Int containing the ending channel number

getfend()

Method to get the ending frequency.

Parameters:None Returns:Float containing the ending frequency

getfstart()

Method to get the starting frequency.

Parameters:None Returns:Float containing the starting frequency

getkey(key)

Method to get a data member by name

Parameters:

key : str

The name of the data member to return

Returns:

various, the contents of the requested item

getstart()

Method to get the starting channel number.

Parameters:None Returns:Int containing the starting channel number

setchans(chans)

Method to set the channel range for the line.

Parameters:

chans : list

Two element list of the channel range for the line

Returns:

None

setend(chan)

Method to set the ending channel number.

Parameters:

chan : int

The ending channel number to set

Returns:

None

setfend(freq)

Method to set the ending frequency.

Parameters:

chan : int

The ending frequency to set

Returns:

None

setfreqs(freqs)

Method to set the frequency range for the line.

Parameters:

chans : list

Two element list of the frequency range for the line

Returns:

None

setfstart(freq)

Method to set the starting frequency.

Parameters:

chan : int

The starting frequency to set

Returns:

None

setkey(name='', value='')

Method to set the key-value pairs for the class. It treats the chans and freqs keywords specially, making sure that the pairs of numbers are properly ordered. All other keys and values are passed directly to the Line superclass setkey.

set keys, two styles are possible:

1. name = {key:val} e.g. setkey({“a”:1})
2. name = “key”, value = val e.g. setkey(“a”, 1)

This method checks the type of the keyword value, as it must remain the same. Also new keywords cannot be added.

Parameters:

name : dictionary or string

Dictionary of keyword value pais to set or a string with the name of a single key

value : any

The value to change the keyword to

Returns:

None

setstart(chan)

Method to set the starting channel number.

Parameters:

chan : int

The starting channel number to set

Returns:

None