First, the code (which I found here: https://github.com/defaultxr/taptempo.py/blob/master/taptempo.py)
#!/usr/bin/env python
from __future__ import print_function
import tty
import termios
from time import time
from sys import stdin
def getchar():
fd = stdin.fileno()
old_settings = termios.tcgetattr(fd)
try:
tty.setraw(stdin.fileno())
ch = stdin.read(1)
finally:
termios.tcsetattr(fd, termios.TCSADRAIN, old_settings)
return ch
def addtime(times):
if type(times) != list:
raise(TypeError)
t = time()
if len(times) == 0:
tdiff = 0 # initial seed
else:
tdiff = t - times[-1][0]
return (t, tdiff)
def averagetimes(times):
averagetime = sum([row[1] for row in times])/float(len(times))
bpm = (1.0/(averagetime/60.0))
return (averagetime, bpm)
def main():
print('Tap a key on each beat. Press q to quit.', end='\r')
times = []
while True:
char = getchar()
if char in ('q', 'Q', '\x1b', '\x03'): # q, Q, ESC, Control+C
print()
quit()
times.append(addtime(times))
if len(times) > 1:
# remove first element if it's either the initial seed
# or when the list reaches max length
if times[0][1] == 0 or len(times) > 16:
del times[0]
(averagetime, bpm) = averagetimes(times)
print("\rDetected BPM: %0.3f (Avg time between each: %0.3fs)"
% (bpm, averagetime), end='')
if __name__ == '__main__':
main()
I get an error saying, "ERROR: Could not find a version that satisfies the requirement termios ERROR: No matching distribution found for termios"
After some research, it turns out, termios comes with Python, but it is not included in the windows distribution (it's only in Linux), since another utility called "Airflow" is also not in windows.
I'm a musician and it looks like a nice very lightweight little app, which would be great for "tempo tapping". Larger programs that include tempo tappers are usually too bulky and unnecessary and sometimes a little slow. So I was just wondering if there is a way I could to get that little app to work in windows?
It's an interesting question, anyway. I have never run across such a "conflict" (if it could be called that) between Windows and Linux in Python.
Related
I'm using raw_input in Python to interact with user in shell.
c = raw_input('Press s or n to continue:')
if c.upper() == 'S':
print 'YES'
It works as intended, but the user has to press enter in the shell after pressing 's'. Is there a way to accomplish what I need from an user input without needing to press enter in the shell? I'm using *nixes machines.
Under Windows, you need the msvcrt module, specifically, it seems from the way you describe your problem, the function msvcrt.getch:
Read a keypress and return the
resulting character. Nothing is echoed
to the console. This call will block
if a keypress is not already
available, but will not wait for Enter
to be pressed.
(etc -- see the docs I just pointed to). For Unix, see e.g. this recipe for a simple way to build a similar getch function (see also several alternatives &c in the comment thread of that recipe).
Actually in the meantime (almost 10 years from the start of this thread) a cross-platform module named pynput appeared.
Below a first cut - i.e. that works with lowercase 's' only.
I have tested it on Windows but I am almost 100% positive that it should work on Linux.
from pynput import keyboard
print('Press s or n to continue:')
with keyboard.Events() as events:
# Block for as much as possible
event = events.get(1e6)
if event.key == keyboard.KeyCode.from_char('s'):
print("YES")
Python does not provide a multiplatform solution out of the box.
If you are on Windows you could try msvcrt with:
import msvcrt
print 'Press s or n to continue:\n'
input_char = msvcrt.getch()
if input_char.upper() == 'S':
print 'YES'
curses can do that as well :
import curses, time
def input_char(message):
try:
win = curses.initscr()
win.addstr(0, 0, message)
while True:
ch = win.getch()
if ch in range(32, 127):
break
time.sleep(0.05)
finally:
curses.endwin()
return chr(ch)
c = input_char('Do you want to continue? y/[n]')
if c.lower() in ['y', 'yes']:
print('yes')
else:
print('no (got {})'.format(c))
To get a single character, I have used getch, but I don't know if it works on Windows.
Instead of the msvcrt module you could also use WConio:
>>> import WConio
>>> ans = WConio.getkey()
>>> ans
'y'
On a side note, msvcrt.kbhit() returns a boolean value determining if any key on the keyboard is currently being pressed.
So if you're making a game or something and want keypresses to do things but not halt the game entirely, you can use kbhit() inside an if statement to make sure that the key is only retrieved if the user actually wants to do something.
An example in Python 3:
# this would be in some kind of check_input function
if msvcrt.kbhit():
key = msvcrt.getch().decode("utf-8").lower() # getch() returns bytes data that we need to decode in order to read properly. i also forced lowercase which is optional but recommended
if key == "w": # here 'w' is used as an example
# do stuff
elif key == "a":
# do other stuff
elif key == "j":
# you get the point
I know this is old, but the solution wasn't good enough for me.
I need the solution to support cross-platform and without installing any external Python packages.
My solution for this, in case anyone else comes across this post
Reference: https://github.com/unfor19/mg-tools/blob/master/mgtools/get_key_pressed.py
from tkinter import Tk, Frame
def __set_key(e, root):
"""
e - event with attribute 'char', the released key
"""
global key_pressed
if e.char:
key_pressed = e.char
root.destroy()
def get_key(msg="Press any key ...", time_to_sleep=3):
"""
msg - set to empty string if you don't want to print anything
time_to_sleep - default 3 seconds
"""
global key_pressed
if msg:
print(msg)
key_pressed = None
root = Tk()
root.overrideredirect(True)
frame = Frame(root, width=0, height=0)
frame.bind("<KeyRelease>", lambda f: __set_key(f, root))
frame.pack()
root.focus_set()
frame.focus_set()
frame.focus_force() # doesn't work in a while loop without it
root.after(time_to_sleep * 1000, func=root.destroy)
root.mainloop()
root = None # just in case
return key_pressed
def __main():
c = None
while not c:
c = get_key("Choose your weapon ... ", 2)
print(c)
if __name__ == "__main__":
__main()
If you can use an external library, blessed (cross platform) can do do this quite easily:
from blessed import Terminal
term = Terminal()
with term.cbreak(): # set keys to be read immediately
print("Press any key to continue")
inp = term.inkey() # wait and read one character
Note that while inside the with block, line editing capabilities of the terminal will be disabled.
Documentation for cbreak, inkey, and an example with inkey.
Standard library solution for Unix-like operating systems (including Linux):
def getch():
import sys, termios
fd = sys.stdin.fileno()
orig = termios.tcgetattr(fd)
new = termios.tcgetattr(fd)
new[3] = new[3] & ~termios.ICANON
new[6][termios.VMIN] = 1
new[6][termios.VTIME] = 0
try:
termios.tcsetattr(fd, termios.TCSAFLUSH, new)
return sys.stdin.read(1)
finally:
termios.tcsetattr(fd, termios.TCSAFLUSH, orig)
This works by putting the terminal into non-canonical input mode before reading from the terminal.
Alternative solution that does not echo the user's input (e.g. if the user presses z, z will not appear on screen):
def getch():
import sys, termios, tty
fd = sys.stdin.fileno()
orig = termios.tcgetattr(fd)
try:
tty.setcbreak(fd) # or tty.setraw(fd) if you prefer raw mode's behavior.
return sys.stdin.read(1)
finally:
termios.tcsetattr(fd, termios.TCSAFLUSH, orig)
Usage example:
print('Press s or n to continue: ', end='', flush=True)
c = getch()
print()
if c.upper() == 'S':
print('YES')
use readchar:
import readchar
key = readchar.readkey()
if key == "a":
print("text")
https://pypi.org/project/readchar/ to webpage
I am wondering how to get Python to validate an input line and complete tasks using the input as it's being typed.
For example:
alphabet = "abcdefghijklmnopqrstuvwxyz"
useralphabet = input("Please enter however much of the alphabet you know:")
while(useralphabet in alphabet):
break
print("You know", 26 - len(useralphabet), "letters of the alphabet!")
Obviously I know this code won't work as intended, but I hope it demonstrates the idea of what I'm trying to do, i.e., get the user to input text until that they have entered is no longer part of the specified string.
The answer depends on your OS (operating system). Usually the OS hands over the input string to python only after you hit the ENTER key. If you need to do it as you type, you may need to invoke some system dependent calls to turn off input buffering.
See Python read a single character from the user for more on this
Here is a working example (Tested with Python 3.8.6 on Linux). See this answer if you need to modify for other systems.
The hinput function reads chars as they are typed and calls on_char for each new character passing both the new char and the entire line.
In my example when the user types x the on_char function returns True which causes the hinput function to stop waiting for new input.
If the user types hello it is autocompleted to hello, world and also terminates hinput
import sys
import termios
import tty
from typing import Callable
def main():
hinput("prompt: ", on_char)
return 0
def on_char(ch: str, line: str) -> bool:
if ch == 'x':
sys.stdout.write('\n')
sys.stdout.flush()
return True
if line+ch == 'hello':
sys.stdout.write("%s, world\n" % ch)
sys.stdout.flush()
return True
return False
def hinput(prompt: str=None, hook: Callable[[str,str], bool]=None) -> str:
"""input with a hook for char-by-char processing."""
fd = sys.stdin.fileno()
old = termios.tcgetattr(fd)
inpt = ""
while True:
sys.stdout.write('\r')
if prompt is not None:
sys.stdout.write(prompt)
sys.stdout.write(inpt)
sys.stdout.flush()
ch = None
try:
tty.setraw(sys.stdin.fileno())
ch = sys.stdin.read(1)
finally:
termios.tcsetattr(fd, termios.TCSADRAIN, old)
if hook is not None and hook(ch, inpt):
break
if ord(ch) == 0x7f: #BACKSPACE
if len(inpt) > 0:
sys.stdout.write('\b \b')
inpt = inpt[:-1]
continue
if ord(ch) == 0x0d: #ENTER
sys.stdout.write('\n')
sys.stdout.flush()
break
if ch.isprintable():
inpt += ch
return inpt
if __name__ == '__main__':
sys.exit(main())
I'm using raw_input in Python to interact with user in shell.
c = raw_input('Press s or n to continue:')
if c.upper() == 'S':
print 'YES'
It works as intended, but the user has to press enter in the shell after pressing 's'. Is there a way to accomplish what I need from an user input without needing to press enter in the shell? I'm using *nixes machines.
Under Windows, you need the msvcrt module, specifically, it seems from the way you describe your problem, the function msvcrt.getch:
Read a keypress and return the
resulting character. Nothing is echoed
to the console. This call will block
if a keypress is not already
available, but will not wait for Enter
to be pressed.
(etc -- see the docs I just pointed to). For Unix, see e.g. this recipe for a simple way to build a similar getch function (see also several alternatives &c in the comment thread of that recipe).
Actually in the meantime (almost 10 years from the start of this thread) a cross-platform module named pynput appeared.
Below a first cut - i.e. that works with lowercase 's' only.
I have tested it on Windows but I am almost 100% positive that it should work on Linux.
from pynput import keyboard
print('Press s or n to continue:')
with keyboard.Events() as events:
# Block for as much as possible
event = events.get(1e6)
if event.key == keyboard.KeyCode.from_char('s'):
print("YES")
Python does not provide a multiplatform solution out of the box.
If you are on Windows you could try msvcrt with:
import msvcrt
print 'Press s or n to continue:\n'
input_char = msvcrt.getch()
if input_char.upper() == 'S':
print 'YES'
curses can do that as well :
import curses, time
def input_char(message):
try:
win = curses.initscr()
win.addstr(0, 0, message)
while True:
ch = win.getch()
if ch in range(32, 127):
break
time.sleep(0.05)
finally:
curses.endwin()
return chr(ch)
c = input_char('Do you want to continue? y/[n]')
if c.lower() in ['y', 'yes']:
print('yes')
else:
print('no (got {})'.format(c))
To get a single character, I have used getch, but I don't know if it works on Windows.
Instead of the msvcrt module you could also use WConio:
>>> import WConio
>>> ans = WConio.getkey()
>>> ans
'y'
On a side note, msvcrt.kbhit() returns a boolean value determining if any key on the keyboard is currently being pressed.
So if you're making a game or something and want keypresses to do things but not halt the game entirely, you can use kbhit() inside an if statement to make sure that the key is only retrieved if the user actually wants to do something.
An example in Python 3:
# this would be in some kind of check_input function
if msvcrt.kbhit():
key = msvcrt.getch().decode("utf-8").lower() # getch() returns bytes data that we need to decode in order to read properly. i also forced lowercase which is optional but recommended
if key == "w": # here 'w' is used as an example
# do stuff
elif key == "a":
# do other stuff
elif key == "j":
# you get the point
I know this is old, but the solution wasn't good enough for me.
I need the solution to support cross-platform and without installing any external Python packages.
My solution for this, in case anyone else comes across this post
Reference: https://github.com/unfor19/mg-tools/blob/master/mgtools/get_key_pressed.py
from tkinter import Tk, Frame
def __set_key(e, root):
"""
e - event with attribute 'char', the released key
"""
global key_pressed
if e.char:
key_pressed = e.char
root.destroy()
def get_key(msg="Press any key ...", time_to_sleep=3):
"""
msg - set to empty string if you don't want to print anything
time_to_sleep - default 3 seconds
"""
global key_pressed
if msg:
print(msg)
key_pressed = None
root = Tk()
root.overrideredirect(True)
frame = Frame(root, width=0, height=0)
frame.bind("<KeyRelease>", lambda f: __set_key(f, root))
frame.pack()
root.focus_set()
frame.focus_set()
frame.focus_force() # doesn't work in a while loop without it
root.after(time_to_sleep * 1000, func=root.destroy)
root.mainloop()
root = None # just in case
return key_pressed
def __main():
c = None
while not c:
c = get_key("Choose your weapon ... ", 2)
print(c)
if __name__ == "__main__":
__main()
If you can use an external library, blessed (cross platform) can do do this quite easily:
from blessed import Terminal
term = Terminal()
with term.cbreak(): # set keys to be read immediately
print("Press any key to continue")
inp = term.inkey() # wait and read one character
Note that while inside the with block, line editing capabilities of the terminal will be disabled.
Documentation for cbreak, inkey, and an example with inkey.
Standard library solution for Unix-like operating systems (including Linux):
def getch():
import sys, termios
fd = sys.stdin.fileno()
orig = termios.tcgetattr(fd)
new = termios.tcgetattr(fd)
new[3] = new[3] & ~termios.ICANON
new[6][termios.VMIN] = 1
new[6][termios.VTIME] = 0
try:
termios.tcsetattr(fd, termios.TCSAFLUSH, new)
return sys.stdin.read(1)
finally:
termios.tcsetattr(fd, termios.TCSAFLUSH, orig)
This works by putting the terminal into non-canonical input mode before reading from the terminal.
Alternative solution that does not echo the user's input (e.g. if the user presses z, z will not appear on screen):
def getch():
import sys, termios, tty
fd = sys.stdin.fileno()
orig = termios.tcgetattr(fd)
try:
tty.setcbreak(fd) # or tty.setraw(fd) if you prefer raw mode's behavior.
return sys.stdin.read(1)
finally:
termios.tcsetattr(fd, termios.TCSAFLUSH, orig)
Usage example:
print('Press s or n to continue: ', end='', flush=True)
c = getch()
print()
if c.upper() == 'S':
print('YES')
use readchar:
import readchar
key = readchar.readkey()
if key == "a":
print("text")
https://pypi.org/project/readchar/ to webpage
I'm doing a project with an embedded computer module, the EXM32 Starter Kit and I want to simulate a piano with 8 musical notes. The OS is linux and I'm programming in Python. My problem is that version of Python is the 2.4 without 'pygame' library to play two sounds simultaneously. At now I am using in python "os.system('aplay ./Do.wav')" to play, from linux console, the sound.
The simplificated question is: Can I use another library to do the same as:
snd1 = pygame.mixer.Sound('./Do.wav')
snd2 = pygame.mixer.Sound('./Re.wav')
snd1.play()
snd2.play()
to play 'Do' and 'Re' simultanously? I can use "auidoop" and "wave" library.
I tried use threading but the problem is that the program wait until the console command has been finished. Another library that can I used? or the method to do with 'wave' or 'audioop'?? (this last library I believe is only for manipulated sound files)
The complete code is:
import termios, sys, os, time
TERMIOS = termios
#I wrote this method to simulate keyevent. I haven't got better libraries to do this
def getkey():
fd = sys.stdin.fileno()
old = termios.tcgetattr(fd)
new = termios.tcgetattr(fd)
new[3] = new[3] & ~TERMIOS.ICANON & ~TERMIOS.ECHO
new[6][TERMIOS.VMIN] = 1
new[6][TERMIOS.VTIME] = 0
termios.tcsetattr(fd, TERMIOS.TCSANOW, new)
key_pressed = None
try:
key_pressed = os.read(fd, 1)
finally:
termios.tcsetattr(fd, TERMIOS.TCSAFLUSH, old)
return key_pressed
def keyspress(note):
if note == DO:
os.system('aplay ./notas_musicales/Do.wav')
elif note == RE:
os.system('aplay ./notas_musicales/Re.wav')
elif note == MI:
os.system('aplay ./notas_musicales/Mi.wav')
elif note == FA:
os.system('aplay ./notas_musicales/Fa.wav')
elif note == SOL:
os.system('aplay ./notas_musicales/Sol.wav')
elif note == LA:
os.system('aplay ./notas_musicales/La.wav')
elif note == SI:
os.system('aplay ./notas_musicales/Si.wav')
DO = 'a'
RE = 's'
MI = 'd'
FA = 'f'
SOL = 'g'
LA = 'h'
SI = 'j'
key_pressed = ""
i = 1
#in each iteration the program enter into the other 'if' to doesn't interrupt
#the last sound.
while(key_pressed != 'n'):
key_pressed = getkey()
if i == 1:
keyspress(key_pressed)
i = 0
elif i == 0:
keyspress(key_pressed)
i = 1
print ord(key_pressed)
Due to the global interpreter lock ("GIL") in the default python implementation only one thread will be running at a time. So that won't help you much in this case.
Additionally, os.system waits for the command to finish, and spawns an extra shell to run the command in. You should use suprocess.Popen instead, which will return as soon as it has started the program, and by default does not spawn an extra shell. The following code should start both players as closely together as possible:
import subprocess
do = subprocess.Popen(['aplay', './notas_musicales/Do.wav'])
re = subprocess.Popen(['aplay', './notas_musicales/Re.wav'])
Your basic problem is that you want to spawn a process and not wait for its return value. You can't do that with os.system() (well you could just spawn dozens of threads).
You can do this with the subprocess module which incidentally is available since 2.4. See here for an example.
I'm using raw_input in Python to interact with user in shell.
c = raw_input('Press s or n to continue:')
if c.upper() == 'S':
print 'YES'
It works as intended, but the user has to press enter in the shell after pressing 's'. Is there a way to accomplish what I need from an user input without needing to press enter in the shell? I'm using *nixes machines.
Under Windows, you need the msvcrt module, specifically, it seems from the way you describe your problem, the function msvcrt.getch:
Read a keypress and return the
resulting character. Nothing is echoed
to the console. This call will block
if a keypress is not already
available, but will not wait for Enter
to be pressed.
(etc -- see the docs I just pointed to). For Unix, see e.g. this recipe for a simple way to build a similar getch function (see also several alternatives &c in the comment thread of that recipe).
Actually in the meantime (almost 10 years from the start of this thread) a cross-platform module named pynput appeared.
Below a first cut - i.e. that works with lowercase 's' only.
I have tested it on Windows but I am almost 100% positive that it should work on Linux.
from pynput import keyboard
print('Press s or n to continue:')
with keyboard.Events() as events:
# Block for as much as possible
event = events.get(1e6)
if event.key == keyboard.KeyCode.from_char('s'):
print("YES")
Python does not provide a multiplatform solution out of the box.
If you are on Windows you could try msvcrt with:
import msvcrt
print 'Press s or n to continue:\n'
input_char = msvcrt.getch()
if input_char.upper() == 'S':
print 'YES'
curses can do that as well :
import curses, time
def input_char(message):
try:
win = curses.initscr()
win.addstr(0, 0, message)
while True:
ch = win.getch()
if ch in range(32, 127):
break
time.sleep(0.05)
finally:
curses.endwin()
return chr(ch)
c = input_char('Do you want to continue? y/[n]')
if c.lower() in ['y', 'yes']:
print('yes')
else:
print('no (got {})'.format(c))
To get a single character, I have used getch, but I don't know if it works on Windows.
Instead of the msvcrt module you could also use WConio:
>>> import WConio
>>> ans = WConio.getkey()
>>> ans
'y'
On a side note, msvcrt.kbhit() returns a boolean value determining if any key on the keyboard is currently being pressed.
So if you're making a game or something and want keypresses to do things but not halt the game entirely, you can use kbhit() inside an if statement to make sure that the key is only retrieved if the user actually wants to do something.
An example in Python 3:
# this would be in some kind of check_input function
if msvcrt.kbhit():
key = msvcrt.getch().decode("utf-8").lower() # getch() returns bytes data that we need to decode in order to read properly. i also forced lowercase which is optional but recommended
if key == "w": # here 'w' is used as an example
# do stuff
elif key == "a":
# do other stuff
elif key == "j":
# you get the point
I know this is old, but the solution wasn't good enough for me.
I need the solution to support cross-platform and without installing any external Python packages.
My solution for this, in case anyone else comes across this post
Reference: https://github.com/unfor19/mg-tools/blob/master/mgtools/get_key_pressed.py
from tkinter import Tk, Frame
def __set_key(e, root):
"""
e - event with attribute 'char', the released key
"""
global key_pressed
if e.char:
key_pressed = e.char
root.destroy()
def get_key(msg="Press any key ...", time_to_sleep=3):
"""
msg - set to empty string if you don't want to print anything
time_to_sleep - default 3 seconds
"""
global key_pressed
if msg:
print(msg)
key_pressed = None
root = Tk()
root.overrideredirect(True)
frame = Frame(root, width=0, height=0)
frame.bind("<KeyRelease>", lambda f: __set_key(f, root))
frame.pack()
root.focus_set()
frame.focus_set()
frame.focus_force() # doesn't work in a while loop without it
root.after(time_to_sleep * 1000, func=root.destroy)
root.mainloop()
root = None # just in case
return key_pressed
def __main():
c = None
while not c:
c = get_key("Choose your weapon ... ", 2)
print(c)
if __name__ == "__main__":
__main()
If you can use an external library, blessed (cross platform) can do do this quite easily:
from blessed import Terminal
term = Terminal()
with term.cbreak(): # set keys to be read immediately
print("Press any key to continue")
inp = term.inkey() # wait and read one character
Note that while inside the with block, line editing capabilities of the terminal will be disabled.
Documentation for cbreak, inkey, and an example with inkey.
Standard library solution for Unix-like operating systems (including Linux):
def getch():
import sys, termios
fd = sys.stdin.fileno()
orig = termios.tcgetattr(fd)
new = termios.tcgetattr(fd)
new[3] = new[3] & ~termios.ICANON
new[6][termios.VMIN] = 1
new[6][termios.VTIME] = 0
try:
termios.tcsetattr(fd, termios.TCSAFLUSH, new)
return sys.stdin.read(1)
finally:
termios.tcsetattr(fd, termios.TCSAFLUSH, orig)
This works by putting the terminal into non-canonical input mode before reading from the terminal.
Alternative solution that does not echo the user's input (e.g. if the user presses z, z will not appear on screen):
def getch():
import sys, termios, tty
fd = sys.stdin.fileno()
orig = termios.tcgetattr(fd)
try:
tty.setcbreak(fd) # or tty.setraw(fd) if you prefer raw mode's behavior.
return sys.stdin.read(1)
finally:
termios.tcsetattr(fd, termios.TCSAFLUSH, orig)
Usage example:
print('Press s or n to continue: ', end='', flush=True)
c = getch()
print()
if c.upper() == 'S':
print('YES')
use readchar:
import readchar
key = readchar.readkey()
if key == "a":
print("text")
https://pypi.org/project/readchar/ to webpage