CASA6

• 

  Josh Marvil 2 days ago a00a67879f3b8170f273d04c57edd889d7b89f91

  CAS-14719: guard against division by zero in getCommonBeam ellipse transform
  _transformEllipseByScaling divides by 2*j1-1 = |u|/sqrt(f1), which is
  exactly zero when the scaled ellipse is circular (u = r - t = 0). That
  is an ordinary geometry, not a degenerate input, but the resulting
  0/0 evaluates to NaN; the enclosing GaussianBeam then fails
  setMajorMinor, and the exception propagates as a failed minor cycle
  in automasking. Reproduced on a 6-channel block whose beams share a
  single float32 minor axis and whose position angles differ by ~1e-8
  rad, so r and t land on the same double.
  
  Take the analytic limit (k = (r+t)/2 +- sqrt(s)) instead of dividing,
  and stop the enclosing-beam retry loop from rebuilding a non-finite
  beam inside its own catch handler. Also correct the circle branch,
  which returned sqrt(k) where the semi-axis is sqrt(1/k); it was
  unreachable before and is reachable now.

  • casatools/src/code/imageanalysis/ImageAnalysis/CasaImageBeamSet.cc (version a00a67879f3b8170f273d04c57edd889d7b89f91) (diffs)