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Last modified: 10 October 2007

URL: http://cxc.harvard.edu/ciao3.4/bugs/dmregrid.html
Hardcopy (PDF): A4 | Letter

Bugs: dmregrid


Bugs

  1. Incorrect physical and world coordinates in the output

  2. Tool does not fail with bad bin syntax (29 Jan 2007)

  3. Negative values are not preserved with "npts!=0" [New](10 Oct 2007)


Bugs

  1. Incorrect physical and world coordinates in the output

    If the lower limits in the bin parameter are set to anything other than 1 - i.e. xlo:xhi:xbin,ylo:yhi:ybin where xlo and/or ylo do not equal 1 - dmregrid fails to update the physical-to-logical coordinate system, which causes both physical and world coordinates to be incorrect in the output file.

  2. Tool does not fail with bad bin syntax (29 Jan 2007)

    If you put column names into the dmregrid "bin" parameter, it creates a large output file instead of failing, e.g.

    unix% dmregrid infile="acis_evt2.fits[bin x=4000:4200:4,y=4000:4200:4]" \
          outfile="test.fits" bin="x=4000:4200:0.5,y=4000:4200:0.5"
    
    unix% dmlist test.fits blocks
     
    ----------------------------------------------------------------------
    Dataset: bug_test.fits
    ----------------------------------------------------------------------
     
         Block Name                          Type         Dimensions
    ----------------------------------------------------------------------
    Block    1: bug_test.fits                  Image      Real4(8408x8408)
    

    The correct bin syntax for this example is:

    bin="4000:4200:0.5,4000:4200:0.5"
    
  3. Negative values are not preserved with "npts!=0" [New](10 Oct 2007)

    In approximation mode, i.e. "npts!=0", dmregrid skips pixels with negative values. With npts == 0 (exact mode), the negative values are preserved.

Hardcopy (PDF): A4 | Letter
Last modified: 10 October 2007


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