RS-tracker/demod/iq_svcl/plot_fft.py

48 wiersze
919 B
Python

import os
import sys
import numpy as np
import matplotlib.pyplot as plt
import matplotlib.ticker as ticker
if len(sys.argv) < 2:
print("usage:")
print("\tpython %s <fft_file.csv>" % sys.argv[0])
sys.exit()
fft_file = sys.argv[1]
if not os.path.isfile(fft_file):
print("error: %s not found" % fft_file)
sys.exit()
raw_data = np.genfromtxt( fft_file, delimiter=',', max_rows=1)
data1 = raw_data[:] # max_rows=2: raw_data[0,:]
print(data1)
db = data1[5:]
sr = -2.0*data1[1]
freq_min = data1[1] / sr
freq_max = data1[2] / sr
fq = np.arange(freq_min, freq_max, 1.0/(data1[4]+1))
N = len(db)
m = np.mean(db)
db5 = np.full(N, m)
for n in range(2, N-2):
db5[n] = (db[n-2]+db[n-1]+db[n]+db[n+1]+db[n+2])/5.0
ax1 = plt.subplot(111)
ax1.set_xlim(fq[0], fq[-1])
ax1.plot( fq, db, color='b', linewidth=0.06, label='fft')
ax1.plot( fq, db5, color='g', linewidth=0.4, label='fft')
plt.show()