python - How can I play a sine/square wave using Pygame?

Question

I'm trying to play a sine wave using Pygame's sndarray.make_sound function. However, when I use this array to play it:

np.sin(2 * np.pi * np.arange(44100) * 440 / 44100).astype(np.float32)

where 440 is the frequency and 44100 is the sample rate, a loud, jarring noise plays instead. This works using pyaudio.PyAudio(), however I need something that doesn't block execution. This happens with square waves, too, however there it just doesn't play anything. I'm using channels=1 for the mixer.pre_init and mixer.init functions.

How can I fix this? If it helps, I'm using a Mac. Thanks in advance!

Answer 1

You can load the numpy array directly to a pygame.mixer.Sound object and play it:

import pygame
import numpy as np

pygame.mixer.init()

buffer = np.sin(2 * np.pi * np.arange(44100) * 440 / 44100).astype(np.float32)
sound = pygame.mixer.Sound(buffer)

sound.play(0)
pygame.time.wait(int(sound.get_length() * 1000))