The Cannon

The Cannon is a data-driven approach to stellar label determination.

The seminal paper describing The Cannon is Ness et al. (2015). The name, The Cannon, derives from Annie Jump-Cannon, who first arranged stellar spectra in order of temperature purely by the data, without the need for stellar models.

This software package is released as part of Casey et al. (2016) and builds on the original implementation of The Cannon by including a number of additional features:

• Easily construct models with complex vectorizers (e.g., cubic polynomial models with 25 labels)
• Analytic derivatives for blazingly-fast optimization at the training step and the test step
• Built-in parallelism to run the training step and the test step in parallel
• Pseudo-continuum normalization using sums of sine and cosine functions
• L1 regularization to discover and enforce sparsity
• Pixel censoring masks for individual labels
• Stratified under-sampling utilities to produce a (more) balanced training set

The Cannon is being actively developed in a public GitHub repository, where you can open an issue if you have any problems.

User Guide

• Installation
  • Stable Version
  • Development Version
  • Testing
• Getting Started Guide
  • Downloading the data
  • Creating a model
  • The training step
  • The test step
  • Saving the model to disk
• Tutorials
  • Constructing the training set
  • Continuum normalization
  • Censoring
  • Regularization
• API
  • CannonModel
  • Censoring
  • Continuum
  • Fitting
  • Utilities
  • Vectorizer
    • BaseVectorizer
    • PolynomialVectorizer
  • tc command line utility

License & Attribution

The source code is released under the MIT license. If you make use of the code, please cite both the original Ness et al. (2015) paper and Casey et al. (2016):

@ARTICLE{Ness_2015
    author = {{Ness}, M. and {Hogg}, D.~W. and {Rix}, H.-W. and {Ho}, A.~Y.~Q. and
        {Zasowski}, G.},
    title = "{The Cannon: A data-driven approach to Stellar Label Determination}",
    journal = {\apj},
    year = 2015,
    month = jul,
    volume = 808,
    eid = {16},
    pages = {16},
    doi = {10.1088/0004-637X/808/1/16},
}

@ARTICLE{Casey_2016
    author = {{Casey}, A.~R. and {Hogg}, D.~W. and {Ness}, M. and {Rix}, H.-W. and
        {Ho}, A.~Q. and {Gilmore}, G.},
    title = "{The Cannon 2: A data-driven model of stellar spectra for detailed chemical abundance analyses}",
    journal = {ArXiv e-prints},
    archivePrefix = "arXiv",
    eprint = {1603.03040},
    year = 2016,
    month = mar,
}

Here is a list of notable publications that have used or developed upon The Cannon:

• Ho et al.
• others