Generate a sine wave and save it in a wav file, works on python 2 and python 3

sine_wave.py

# #MIT License

# Copyright (c) [2018] [Alessandro Cudazzo, Francesco Capuzzolo]

# Permission is hereby granted, free of charge, to any person obtaining a copy
# of this software and associated documentation files (the "Software"), to deal
# in the Software without restriction, including without limitation the rights
# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
# copies of the Software, and to permit persons to whom the Software is
# furnished to do so, subject to the following conditions:

# The above copyright notice and this permission notice shall be included in all
# copies or substantial portions of the Software.

# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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# SOFTWARE.

# Generate a sine wave and save it in a wav file.
# works on python 2 and python 3
#
# without agruments the behaviour generate a sine_wave.wav file
# 10 sec, 400hz, mono, volume = 10
#
# optional arguments:
#	-h, --help    show this help message and exit
# 	-s            set stereo mode; if missing, the file will be saved in mono
#	-t DURATION   set sine wave's duration in seconds
#	-f FREQUENCY  set sine wave's frequency [0,20000]Hz
#	-v VOLUME     set sine wave's amplitude [1,10]
#	-o OUTPUT     set name of wav file
import argparse, math, wave, struct

parser = argparse.ArgumentParser(description='Generate a sine wave.')

parser.add_argument('-s', action='store_true', help='set stereo mode; if missing, the file will be saved in mono', default=False, dest='stereo')
parser.add_argument('-t', action='store', type=float, help='set sine wave\'s duration in seconds', default=10.0, dest='duration')
parser.add_argument('-f', action='store', type=float, help='set sine wave\'s frequency [0,20000]Hz', default=400.0, dest='frequency')
parser.add_argument('-v', action='store', type=float, help='set sine wave\'s amplitude [1,10]', default=10, dest='volume')
parser.add_argument('-o', action='store', help='set name of wav file', default='sine_wave.wav', dest='output')

args = parser.parse_args()

IS_STEREO = args.stereo
SAMPLE_RATE = 44100.0 		# hertz
NUM_SECONDS = args.duration  	# seconds
FREQUENCY = args.frequency    	# hertz
VOLUME = args.volume * 100
OUTPUT_FILE = args.output 	# filepath

assert NUM_SECONDS > 0.0, 'Duration must be higher than 0 seconds.'
assert 0 <= FREQUENCY <= 20000.0, 'Wave frequency must be positive and lesser than 20000 Hz.'
assert 100 <= VOLUME <= 1000.0, 'Volume must be higher than 0 and lesser than 100.'

log = (
	'Generating a sine wave.\n\tSample rate: '+str(SAMPLE_RATE)+
	' Hz\n\tDuration: '+ str(NUM_SECONDS)+
	' s\n\tFrequency: '+str(FREQUENCY)+ 
	' Hz\n\tStereo: '+str(IS_STEREO)+
	'\n\tVolume: '+str(VOLUME)+
	'\n\tDestination: '+str(OUTPUT_FILE)
	)

print (log)

file = wave.open(OUTPUT_FILE,'wb')
file.setnchannels(2 if IS_STEREO else 1)
file.setsampwidth(2) 
file.setframerate(SAMPLE_RATE)

for i in range(int(NUM_SECONDS * SAMPLE_RATE)):
	value = int(VOLUME * math.sin(2 * FREQUENCY * math.pi * float(i) / float(SAMPLE_RATE)))
	data = struct.pack('<hh', value, value) if IS_STEREO else struct.pack('<h', value)
	file.writeframesraw(data)

file.close()

Alessandro,
I am using your code. I changed VOLUME = 32767 to allow for maximum audio volume in the WAV file. I have been trying to get better accuracy of higher frequency waves and finally figured out that the SAMPLERATE was too low.