Unable to load fits.bz2 file #3881

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1. embray

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   io.fits

   on Jun 24, 2015
2. embray commented on Jun 24, 2015

   

   embray

   on Jun 24, 2015

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   Hi @eddedmondson,

   The version of Astropy you're using does not support transparent reading from bz2 files. This was only added very recently in the development version (#3789) and will be available in Astropy v1.1.0.
3. embray

   closed this as completedon Jun 24, 2015
4. embray commented on Jun 24, 2015

   

   embray

   on Jun 24, 2015

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   By the way, as a current workaround you can still Python's bz2 library and pass an open bz2 file in to fits.open(), which will generally work with any stream-like object:

   In [1]: import astropy
   
   In [2]: astropy.__version__
   Out[2]: '1.0.3'
   
   In [3]: from astropy.io import fits
   
   In [4]: import bz2
   
   In [5]: f = bz2.open('astropy/io/fits/tests/data/tb.fits.bz2')
   
   In [6]: h = fits.open(f)
   
   In [7]: h.info()
   Filename: <class 'bz2.BZ2File'>
   No.    Name         Type      Cards   Dimensions   Format
   0    PRIMARY     PrimaryHDU      11   ()              
   1                BinTableHDU     24   2R x 4C      [1J, 3A, 1E, 1L]   
   
   In [8]: h[1].data
   Out[8]: 
   FITS_rec([(1, 'abc', 3.7000000715255736, False),
          (2, 'xy', 6.6999997138977054, True)], 
         dtype=[('c1', '>i4'), ('c2', 'S3'), ('c3', '>f4'), ('c4', 'i1')])

   The only difference in the new version is that it can detect bz2 files automatically from the filename and/or contents and do this automatically.
5. PaulKuin commented on Aug 21, 2015

   

   PaulKuin

   on Aug 21, 2015

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   I just had a similar problem with an ESO file that had been compressed (.Z) Error reported was "Header missing END card."
6. embray commented on Aug 21, 2015

   

   embray

   on Aug 21, 2015

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   @PaulKuin Regarding "Header missing END card": #3941
7. PaulKuin commented on Aug 21, 2015

   

   PaulKuin

   on Aug 21, 2015

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   Hi Erik,

   Ah, but the message was in error! There was an 'end' card (I ran also
   fverify on it and that gave no errors). [I assume you know the ftools]. It
   is an error message that pops up when the file is compressed. Imho I think
   fits.open should read the first few characters to see if this is a
   compressed file. Actually, I'm kind of surprised, since the fits file
   should start with "SIMPLE = T", but apparently that check gets passed (or
   not done perhaps?). Anyway, sorry to add to your burden, but something can
   be improved there with the error trapping.

   Well, over there it must be about time to leave for the weekend, so let me
   wish you a good one!

   Paul

   On Fri, Aug 21, 2015 at 7:33 PM, Erik Bray [email protected] wrote:

   @PaulKuin https://github.com/PaulKuin Regarding "Header missing END
   card": #3941 #3941

   —
   Reply to this email directly or view it on GitHub
   #3881 (comment).

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8. embray commented on Aug 21, 2015

   

   embray

   on Aug 21, 2015

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   Right, that's what was discussed in #3941.
9. embray commented on Aug 21, 2015

   

   embray

   on Aug 21, 2015

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   And thanks, you have a good one too!