#!/usr/bin/env python3

import sys

import numpy as np
import matplotlib.pyplot as pp

with open(sys.argv[1], 'rb') as infile:
    header = infile.read(4)
    if header == b'CPX_':
        T = np.fromfile(infile, dtype=np.float32, count=1)
        data = np.fromfile(infile, dtype=np.complex64)
    else:
        print(f"Error: Format {header} not implemented yet.")
        exit(1)

    t = np.arange(0, T*data.size, T)

    amp = np.absolute(data)
    phase = np.unwrap(np.angle(data))

    pp.plot(t, amp, 'r-')
    pp.legend(['Amplitude'])
    pp.twinx()
    pp.plot(t, phase, 'b-')
    pp.legend(['Phase [radians]'])
    pp.xlabel('Time [s]')
    pp.show()