25 lines
644 B
Python
Executable File
25 lines
644 B
Python
Executable File
#!/usr/bin/env python3
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import sys
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import numpy as np
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import matplotlib.pyplot as pp
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with open(sys.argv[1], 'rb') as infile:
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header = infile.read(4)
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if header != b'CPX_':
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print(f"Error: not a complex signal file. Format {header} not implemented yet.")
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exit(1)
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T = np.fromfile(infile, dtype=np.float32, count=1)
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data = np.fromfile(infile, dtype=np.complex64)
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f = np.arange(-1/(2*T), 1/(2*T), 1/T/data.size)[:data.size]
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spec = 20*np.log10(np.absolute(np.fft.fftshift(np.fft.fft(data))) / data.size)
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pp.plot(f, spec, 'b-')
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pp.legend(['Spectrum'])
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pp.xlabel('Frequency [Hz]')
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pp.show()
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