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Last modified: 10 October 2007

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

Bugs: dmcopy


A list of bugs fixed in CIAO 3.4 is available.


Caveats

  1. Creating a filter for data that is outside the range of TLMIN:TLMAX

Bugs

  1. Rebinning an image with different values for the two axes causes the coordinate information to be lost

  2. The BLANK header keyword that an older version of some FTOOLs (e.g. chimgtyp) write to the FITS file header causes problems for dmcopy.

  3. The tool always copies the data in the primary image, even when "[opt all]" is not used.

  4. Specifying a fixed number of output image bins (06 Mar 2007)

  5. The tool only copies the first element of a vector array column (06 Mar 2007)

  6. # DMCOPY (CIAO 3.4): Can't convert region filter using unequal scaling factors.
    Pixels outside region will not be set to null. (10 Oct 2007)


Caveats

  1. Creating a filter for data that is outside the range of TLMIN:TLMAX

    If data in a table is outside the valid range of TLMIN:TLMAX, it is impossible to select it with a filter except by doing

    [exclude foo=:]
    

Bugs

  1. Rebinning an image with different values for the two axes causes the coordinate information to be lost

    For example:

    unix% dmcopy acis.img"[bin x=::5,y=::6]" acis5x6.img
    

    Using the same value for both axes works correctly:

    unix% dmcopy acis.img"[bin (x,y)=::5]" acis5.img
    
  2. The BLANK header keyword that an older version of some FTOOLs (e.g. chimgtyp) write to the FITS file header causes problems for dmcopy.

    Workarounds:

    1. Use a CIAO tool in place of the FTOOL that created the BLANK keyword, e.g. instead of chimgtyp, try

      unix% dmcopy input.fits"[opt type=i4,null=-9999]" output.fits 
      

      changing the opt type as appropriate.

    2. Delete the BLANK keyword before passing the file to dmcopy or any other CIAO tool.

  3. The tool always copies the data in the primary image, even when "[opt all]" is not used.

    For example:

    unix% dmcopy acis.fits"[spectrum]" spectrum.fits
    unix% dmlist spectrum.fits blocks 
     
    --------------------------------------------------------------------------------
    Dataset: spectrum.fits
    --------------------------------------------------------------------------------
     
         Block Name                          Type         Dimensions
    --------------------------------------------------------------------------------
    Block    1: WMAP                           Image      Int2(1024x1024)
    Block    2: SPECTRUM                       Table         5 cols x 1024     rows
    ...
    

    Here we expected to only get the SPECTRUM block, not the as WMAP well.

    Workaround:

    There is an odd sort of workaround:

    unix% dmtcalc acis.fits spectrum2.fits expr="(1==1)"
    unix% dmlist spectrum2.fits blocks 
     
    --------------------------------------------------------------------------------
    Dataset: spectrum2.fits
    --------------------------------------------------------------------------------
     
         Block Name                          Type         Dimensions
    --------------------------------------------------------------------------------
    Block    1: PRIMARY                        Null        
    Block    2: SPECTRUM                       Table         5 cols x 1024     rows
    ...
    
  4. Specifying a fixed number of output image bins (06 Mar 2007)

    The number of bins that dmcopy creates is different than the input specification:

    unix% dmcopy acis_evt2.fits"[bin x=3482:4708:#122,y=3406:4630:#122]" test.fits
    
    unix% dmlist test.fits blocks
    ....
    Block    1: EVENTS_IMAGE                   Image      Int2(123x122)
    ...
    
  5. The tool only copies the first element of a vector array column (06 Mar 2007)

    For example, in this file, there is a WCS on the POS column which is a vector array column that is 13 elements long. Copying the data yields:

    unix% dmcopy acis_fov.fits"[cols ra,dec]" copy.fits
    
    unix% dmlist copy.fits data
     
    --------------------------------------------------------------------------------
    Data for Table Block FOV
    --------------------------------------------------------------------------------
     
    ROW    EQPOS(RA,DEC)
     
         1 (      246.8650071199,      -24.6144174326)
         2 (      246.9897042111,      -24.7220983076)
         3 (      246.6804146459,      -24.4408800569)
         4 (      246.8046771385,      -24.5486314727)
         5 (      246.6736578338,      -24.4347154624)
    

    There should be five rows with 13 cells per row.

  6. # DMCOPY (CIAO 3.4): Can't convert region filter using unequal scaling factors.
    Pixels outside region will not be set to null. (10 Oct 2007)

    This error is printed when the pixels in the input image are not square, e.g. if an exposure map is created with the binning xygrid="3175.0:4555.0:#690,3609.0:4983.0:#690" (1380x1374).

    Workaround:

    Rebin to make an image with square pixels.


Bugs fixed in CIAO 3.4

The following is a list of bugs that were fixed in the CIAO 3.4 software release.

  1. If an invalid kernel name is given, the tool defaults to kernel=fits.

    No error message is printed.

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


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