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Last modified: 21 September 2006

URL: http://cxc.harvard.edu/sherpa3.4/bugs/io_write.html
Hardcopy (PDF): A4 | Letter

I/O Bugs: write


Bugs

  1. The write command does not record faked data in the MDL file.

  2. The background model stack and background model components are not written to the MDL file when "write mdl" is issued.

  3. If the output file already exists, "write mdl" won't clobber it.

  4. The command "write model file.fits fitsimage" does not work after "notice all" is issued (i.e. no file is created).

  5. The write command automatically crops the image to the largest size that will still contain all noticed regions.

  6. For 2D data, "write model file.fits fitsbin" creates tables with the same column name.

  7. WRITE ... PHA forces the output to be COUNTS, regardless of the setting of PLOTY.


Bugs

  1. The write command does not record faked data in the MDL file.

  2. The background model stack and background model components are not written to the MDL file when "write mdl" is issued.

  3. If the output file already exists, "write mdl" won't clobber it.

    Instead, it will write the MDL_Data and MDL_Models blocks to two separate files named "MDL_Data" and "MDL_Models", respectively. The behavior is the same regardless of the setting of sherpa.clobber.

  4. The command "write model file.fits fitsimage" does not work after "notice all" is issued (i.e. no file is created).

  5. The write command automatically crops the image to the largest size that will still contain all noticed regions.

    This means that all images to which the spatial filtering is applied, namely the data and the model image, are cropped upon write-out. Unfortunately this is not true for the exposure map image, which remains at its original size. The result is that it is difficult to work with the saved images, as they don't cover the same regions anymore.

  6. For 2D data, "write model file.fits fitsbin" creates tables with the same column name.

    unix% dmlist file.fits cols
     
    --------------------------------------------------------------------------------
    Columns for Table Block file.fits
    --------------------------------------------------------------------------------
     
    ColNo  Name                 Unit        Type             Range
       1   Bin                  none         Real8          -Inf:+Inf            none
       2   Bin                  none         Real8          -Inf:+Inf            none
       3   Counts               none         Real8          -Inf:+Inf            none
    
  7. WRITE ... PHA forces the output to be COUNTS, regardless of the setting of PLOTY.

    Thus one cannot write out count rates in PHA-format files from Sherpa.

Hardcopy (PDF): A4 | Letter
Last modified: 21 September 2006


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