#!/usr/bin/env python3

import numpy as np
from scipy import signal
from scipy.fft import fft, fftshift
import matplotlib.pyplot as plt

window = signal.windows.flattop(2500)
plt.plot(window)
plt.title("Flat top window")
plt.ylabel("Amplitude")
plt.xlabel("Sample")

plt.figure()
A = fft(window,65536) / (len(window)/2.0)
freq = np.linspace(-0.5*2500, 0.5*2500, len(A))
response = 20 * np.log10(np.abs(fftshift(A / abs(A).max())))
plt.plot(freq, response)
#plt.axis([-0.5, 0.5, -120, 0])
plt.title("Frequency response of the flat top window")
plt.ylabel("Normalized magnitude [dB]")
plt.xlabel("Normalized frequency [cycles per window]")

plt.show()