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Plik wejściowy: a4_633M_3M0.raw

Próba konwersji do formatu .fil (filterbank) za pomocą bin2fil zakończyła się błędem, chociaż plik wyjściowy został utworzony:

Wartość parametru -f (center frequency) została dobrana eksperymentalnie. Przy podaniu wartości rzeczywistej (633MHz), bin2fil generował następujęce wpisy w nagłówku pliku .fil:

Central freq (MHz) = 637.5            
Low channel (MHz) = 636.06           
High channel (MHz) = 638.94

Ostatecznie próba konwersji wyglądała tak:

$ time bin2fil -f 628.5 -sr 3000000 -o a4_633M_3M0.raw.fil a4_633M_3M0.raw 
conversion parameters:
conv_start     0
conv_len       7200
mjd_time       -1
filt_h         0.1
filt_l         60.0
ampli          3.0
channels       25
sample_rate    3000000
center_freq    628.5
source_name    B0329+54
source_ra      33259.37
source_de      543443.57
sr_error       3.0
input_file     a4_633M_3M0.raw
out_file       a4_633M_3M0.raw.fil
chunk_size     50000
Traceback (most recent call last):70%)  ( 99%)
  File "/home/thomson/radio/bin2fil-py/bin2fil.py", line 313, in <module>
    main()
  File "/home/thomson/radio/bin2fil-py/bin2fil.py", line 308, in main
    elaborate(chunk_size, debug=False)
  File "/home/thomson/radio/bin2fil-py/bin2fil.py", line 276, in elaborate
    d = d.reshape(-1, channels).transpose()
ValueError: cannot reshape array of size 1032112 into shape (25)

real	27m7,173s
user	7m40,673s
sys	0m24,698s

Inspekcja pliku za pomocą readfile z pakietu Presto wykazała:

$ readfile a4_633M_3M0.raw.fil 
Assuming the data is a SIGPROC filterbank file.


1: From the SIGPROC filterbank file 'a4_633M_3M0.raw.fil':
                  Telescope = Fake
                Source Name = B0329+54
                    Backend = Unknown
            Obs Date String = 2021-09-29T19:44:30.7096
             MJD start time = 59486.82257765707618
                   RA J2000 = 03:32:59.3700
             RA J2000 (deg) = 53.247375        
                  Dec J2000 = 54:34:43.5700
            Dec J2000 (deg) = 54.5787694444444 
                  Tracking? = True
              Azimuth (deg) = 7.410985e-323
           Zenith Ang (deg) = 6.947696e-310
            Number of polns = 2 (summed)
           Sample time (us) = 111111.444444444 
         Central freq (MHz) = 633              
          Low channel (MHz) = 631.56           
         High channel (MHz) = 634.44           
        Channel width (MHz) = 0.12             
         Number of channels = 25
      Total Bandwidth (MHz) = 3                
                       Beam = 1 of 1
            Beam FWHM (deg) = 1.000
         Spectra per subint = 2400
           Spectra per file = 1090850000
      Time per subint (sec) = 266.667466667
        Time per file (sec) = 121205919.172
            bits per sample = 8
          Are bytes signed? = False
          bytes per spectra = 25
        samples per spectra = 25
           bytes per subint = 60000
         samples per subint = 60000
                zero offset = 0                
           Invert the band? = False
       bytes in file header = 238