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XMM-Newton Science Analysis System


ommosaic (ommosaic-2.11) [xmmsas_20211130_0941-20.0.0]

Testing

Ommosaic contains a test-harness that can check any of the following things:
  1. That a list of sky images derived from a master image have been properly aligned and stacked.
  2. That a list of unrotated images derived from a master image have been properly aligned and stacked.
  3. That a list of sky-images derived from a master sky-image have been properly stacked.
  4. That a list of unrotated images derived from a master sky image have been properly stacked.

Due to time constraints, only the two first of these tests are done when the package is built. The latter two can be done by editing the program createtest.cc in the directory test.

A program createst.cc does the following

  1. Creates a 256x256 test image file (test.fits), with a random background (1-500) and a random number of point-sources (10-100) at random positions on the image.
  2. A master unrotated image file (test1.fits) is cloned from test.fits and FITS header keywords such as WINDOWX0, WINDOWY0 are added to it.

  3. 10 Unrotated-images files are cloned from test1.fits, and the FITS keywords WINDOWX0 and WINDOWY0 are given random small offsets.

  4. A master sky image file (test2.fits) is cloned from test.fits and FITS header keywords such as CRPIX, CRVAL1 are added to it.

  5. 10 Sky-images files are cloned from test2.fits, and the FITS keywords CRPIX1 and CRPIX2 are given random small offsets.

  6. Ommosaic is run on test1.fits and test2,fits to produce output files test3.fits and test4.fits.

  7. A program called checkoutput.cc compares test3.fits with test1.fits- it checks that the image dimensions are the same as well as each corresponding image pixels. Any differences (beyond rounding errors, etc) are reported and the test is deemed to have failed.

  8. checkooutput.cc then compares test4.fits with test2.fits, and does the same tests as before.

For program development testing the number of images can be increased and the image dimensions, etc, changed.

XMM-Newton SOC -- 2021-11-30