#! /usr/bin/env python3


from scipy import signal
import numpy as np
import matplotlib.pyplot as plt

count = 6

sample_rate = 44100
freq = 1000
timescale = 0.002

samples = np.arange( timescale * sample_rate) / sample_rate

def generate_sine( factor = 1):
    amplitude = 1.0 / factor
    frequency = freq * factor
    return amplitude  *  np.sin( 2 * np.pi * samples * frequency)

def generate_rect( max_harmonic = 1):
    harmonic = 1
    signal = generate_sine( harmonic)
    while harmonic < max_harmonic:
        harmonic += 2
        signal += generate_sine( harmonic)
    return signal


fig = plt.figure(1, figsize=( 6, count * 3))
fig.subplots_adjust( hspace = 0.5)

hoehe, breite = count, 1
for index in range( count):
    harmonic = index * 2 + 1
    plt.subplot( hoehe, breite, index + 1)
    plt.title( 'mit %d. Oberw.' % harmonic, loc = 'right', y = 0.5)
    plt.step( generate_rect( harmonic), '.')

plt.show()