1.95. identifyLinesCatalog

Full Name: herschel.hifi.dp.tools.IdentifyLinesCatalogTask
Alias: identifyLinesCatalog
Type: Jython Task - Jython Task
Import: from herschel.hifi.dp.tools import IdentifyLinesCatalogTask

Description

Automatic line identification from a given catalog.

Identify the catalog line list by comparing them with the given CASSIS line list. The resulting lines are objects (Line class) with specific attributes and methods for handling them individually. They are stored in a convenient data structure (Linelist class) that allow global manipulations of all the lines. (cf examples)

Examples

Example 1: # Example run on an ad hoc line catalogue "tds" from the SPIRE Feature Catalogue
lines = identifyLinesCatalog(catalog=tdsSpire, vlsr=-35.0, tolerance=100.0)
Example 2: # Turn output into Herschel Spectrum Line List table dataset
# You need to isolate the observation context and spectrum that lead to the catalog passed above
hsll = exportLines(lines=lines, obs=obs, spectrum=spectrum, author='DT')
# hsll then contains four TDS: 
#  - one for summary (hsll["resume"])
#  - one for identified lines (hsll["identified"])
#  - one for unidentified lines (hsll["unidentified"])
#  - one for detected lines (hsll["detected"])

API details

Properties

TableDataset catalog [INPUT, MANDATORY, default=None]

The catalog to use or the path to the file. The TableDataset input parameter for "catalog" must at least contain the following columns: - A column informing about the line frequency: the column name has to be one of "frequency", "wavelength" or "wavenumber". Ideally, a unit should also provided, however, if no unit is given, the task will assume those are GHz, micrometer or cm-1 respectively. - A column informing about the signal-to-noise ratio, and named "snr". In addition, the TableDataset can also have some more optional columns that will be reflected in the output table: - A column informing about the error applying to the line frequency: the column name has to be one of "frequencyerror", "wavelengtherror" or "wavenumbererror". Ideally, a unit should also provided, however, if no unit is given, the task will assume those are GHz, micrometer or cm-1 respectively. - A column informing about the type of spectrograph: "detector" (for single position data) or "array" (when data are attached to a multi-pixel data-set).

String knownLines [INPUT, MANDATORY, default=None]

The path to the CASSIS linelist file. If no linelist is provided, a default linelist is chosen.

Double vlsr [INPUT, MANDATORY, default=None]

The vlsr of the source in km/s

Double tolerance [INPUT, MANDATORY, default=None]

The tolerance for the lines in km/s. Used in the comparison step.

PyDictionary lines [OUTPUT, MANDATORY, default=None]

* the linelists objects for the lines - detected - identified - unidentified

History

  • MB-30/03/2016: Create the task.
  • MB-09/11/2016: Some improvement on the documentation.