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LSSTDESC / descwl-shear-sims

simple simulations for testing weak lensing shear measurement
BSD 3-Clause "New" or "Revised" License
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input galaxy index in truth_info #210

Closed mr-superonion closed 1 month ago

mr-superonion commented 2 months ago

This PR make the following updates:

  1. Add input galaxy index in truth_info;
  2. Add unit test for the truth_info catalog;
  3. Add one option in the simulation that do not add image noise to simulate noiseless images.
mr-superonion commented 2 months ago

It seems to me that this line combines the bright_object_info arrays from all the bands and make a very long array. @esheldon , Is it better to separate to different keys in a dictionary for each band? In addition, this line also returns a long array of input galaxy info combining all the bands..

mr-superonion commented 1 month ago

There is a one-pixel offset in the truth_info catalog. See the figure below for demonstration. The red dot is the output in the truth_info catalog, which is offset from the center of the galaxy (blue dot). The LSST pipeline also detect the blue as the center. This is because Galsim uses a different convention to python and LSST pipeline. Galsim starts from 1 but the other two start from 0. image

mr-superonion commented 1 month ago

@zhouconghao , @esheldon, @beckermr , Can you please review the PR and merge?

esheldon commented 1 month ago

Yes it would be OK to make those dictionaries, keyed by band