acousticVelocityAndDelayUsingFuture.py

#!/usr/bin/env python

# Version 1.4.1 / 05-February-2018

# Calculate acoustic velocity in air based on temperature. Calculate resulting delay time
# in milliseconds for a measured distance. Results rounded to two decimal places.
# NOTE: there is no method for factoring in gas density in air. Returned values are suitable
# for indoor use where temperature and humidity swings are not extreme.

# This script uses Future additions from http://www.python-future.org

# Import Future additions
from __future__ import absolute_import, division, print_function, unicode_literals
from builtins import input

title='Acoustic Velocity and Loudspeaker Delay Calculator'
print(title)
print('=' * 80)

# Prompt for user input
temp_fahrenheit = float(input("Enter temperture in degrees Fahrenheit: "))
measured_distance = float(input("Enter measured distance between speakers in feet: "))

# Convert Fahrenheit to degrees Celsius
temp_celsius = (temp_fahrenheit - 32) * 5/9      

# Calculate acoustic velocity in meters/second
meters_seconds = (temp_celsius * 0.606) + 331.3    

# Convert meters/second to feet/millisecond
feet_milliseconds = meters_seconds * 0.00328084  

# Calculate time differential based on acoustic velocity and measured distance
delay_time = measured_distance / feet_milliseconds

# Round returned values to two decimal places - suitable for most loudspeaker processing hardware and software.
meters_seconds_round = str(round(meters_seconds, 4))
feet_milliseconds_round = str(round(feet_milliseconds, 4))
delay_time_round = str(round(delay_time, 4))

# Display results
print('=' * 80)
print('Approximate acoustic velocity is:') 
print(meters_seconds_round, 'm/s, or', feet_milliseconds, 'ft/ms.')
print()
print('Approximate delay time is', delay_time_round, 'ms.')
print()
print('Press any key to exit.')
input()