gh-105052:update timeit function's description (#105060)

---------
Co-authored-by: Terry Jan Reedy <tjreedy@udel.edu>
This commit is contained in:
R 2023-08-27 15:22:27 +08:00 committed by GitHub
parent 1ac64237e6
commit 7096a2be33
No known key found for this signature in database
GPG Key ID: 4AEE18F83AFDEB23
3 changed files with 17 additions and 8 deletions

View File

@ -86,9 +86,11 @@ The module defines three convenience functions and a public class:
.. versionchanged:: 3.7
Default value of *repeat* changed from 3 to 5.
.. function:: default_timer()
The default timer, which is always :func:`time.perf_counter`.
The default timer, which is always time.perf_counter(), returns float seconds.
An alternative, time.perf_counter_ns, returns integer nanoseconds.
.. versionchanged:: 3.3
:func:`time.perf_counter` is now the default timer.
@ -124,7 +126,7 @@ The module defines three convenience functions and a public class:
Time *number* executions of the main statement. This executes the setup
statement once, and then returns the time it takes to execute the main
statement a number of times, measured in seconds as a float.
statement a number of times. The default timer returns seconds as a float.
The argument is the number of times through the loop, defaulting to one
million. The main statement, the setup statement and the timer function
to be used are passed to the constructor.

View File

@ -50,9 +50,9 @@ Functions:
"""
import gc
import itertools
import sys
import time
import itertools
__all__ = ["Timer", "timeit", "repeat", "default_timer"]
@ -77,9 +77,11 @@ def inner(_it, _timer{init}):
return _t1 - _t0
"""
def reindent(src, indent):
"""Helper to reindent a multi-line statement."""
return src.replace("\n", "\n" + " "*indent)
return src.replace("\n", "\n" + " " * indent)
class Timer:
"""Class for timing execution speed of small code snippets.
@ -166,7 +168,7 @@ class Timer:
To be precise, this executes the setup statement once, and
then returns the time it takes to execute the main statement
a number of times, as a float measured in seconds. The
a number of times, as float seconds if using the default timer. The
argument is the number of times through the loop, defaulting
to one million. The main statement, the setup statement and
the timer function to be used are passed to the constructor.
@ -228,16 +230,19 @@ class Timer:
return (number, time_taken)
i *= 10
def timeit(stmt="pass", setup="pass", timer=default_timer,
number=default_number, globals=None):
"""Convenience function to create Timer object and call timeit method."""
return Timer(stmt, setup, timer, globals).timeit(number)
def repeat(stmt="pass", setup="pass", timer=default_timer,
repeat=default_repeat, number=default_number, globals=None):
"""Convenience function to create Timer object and call repeat method."""
return Timer(stmt, setup, timer, globals).repeat(repeat, number)
def main(args=None, *, _wrap_timer=None):
"""Main program, used when run as a script.
@ -269,7 +274,7 @@ def main(args=None, *, _wrap_timer=None):
timer = default_timer
stmt = "\n".join(args) or "pass"
number = 0 # auto-determine
number = 0 # auto-determine
setup = []
repeat = default_repeat
verbose = 0
@ -286,7 +291,7 @@ def main(args=None, *, _wrap_timer=None):
time_unit = a
else:
print("Unrecognized unit. Please select nsec, usec, msec, or sec.",
file=sys.stderr)
file=sys.stderr)
return 2
if o in ("-r", "--repeat"):
repeat = int(a)
@ -320,7 +325,7 @@ def main(args=None, *, _wrap_timer=None):
msg = "{num} loop{s} -> {secs:.{prec}g} secs"
plural = (number != 1)
print(msg.format(num=number, s='s' if plural else '',
secs=time_taken, prec=precision))
secs=time_taken, prec=precision))
try:
number, _ = t.autorange(callback)
except:
@ -371,5 +376,6 @@ def main(args=None, *, _wrap_timer=None):
UserWarning, '', 0)
return None
if __name__ == "__main__":
sys.exit(main())

View File

@ -0,0 +1 @@
Update ``timeit`` doc to specify that time in seconds is just the default.