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  1. Data Management
  2. DM-15560

Chi^2 in PSF modeling all get set to NAN

    Details

    • Type: Story
    • Status: To Do
    • Resolution: Unresolved
    • Fix Version/s: None
    • Component/s: meas_algorithms
    • Labels:
      None
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    • Team:
      Data Release Production

      Description

      When running processCcd.py in --debug (lsstDebug) mode, during the PSF modeling stage, a ds9 image titled "Stars & residuals" is displayed showing a mosaic with stars and their residuals (PSF model - data) along with their associated chi^2 values.  However, despite the residuals looking quite good in most cases, all chi^2 values are labelled nan.

      The nan is set here (implying a computed chi2 > 1e100) and an example image looks like:

      I don’t know if this affects anything in the actual algorithm, but it seems the chi^2 is not being set (computed?) properly for the purpose of the debug plots, which can be misleading and muddies much of their diagnostic power.  Please fix.

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            • Assignee:
              Unassigned
              Reporter:
              lauren Lauren MacArthur
              Watchers:
              John Swinbank, Lauren MacArthur, Robert Lupton, Yusra AlSayyad
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              • Created:
                Updated:

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