此代码返回速度慢,输出不同:
from numba import jit
from timeit import default_timer as timer
def fibonacci(n):
a, b = 1, 1
for i in range(n):
a, b = a+b, a
return a
fibonacci_jit = jit(fibonacci)
让我们开始测试
start = timer()
print fibonacci(100)
duration = timer() - start
让我们开始测试
startnext = timer
我正在尝试为Stata .do文件中执行的python函数实现多处理。
在python中,我只需执行一些耗时的简单函数:
import multiprocessing as mp
from timeit import default_timer as timer
def square(x):
return x ** x
# Non-parallel
start = timer()
[square(x) for x in range(0,1000)]
print("Simple execution took {:.2f} seconds".format(timer(
为什么可变字符串比不可变字符串慢?
编辑:
>>> import UserString
... def test():
... s = UserString.MutableString('Python')
... for i in range(3):
... s[0] = 'a'
...
... if __name__=='__main__':
... from timeit import Timer
... t = Timer("test()", "fr
我需要z中的索引值与MATLAB中的索引值相同,我认为在Matlab中这意味着991在Python中为990。
原MATLAB代码(z = 991)
z = 1;
for i = 1:15
test_timer1 = 1;
for tester1 = 1:12
test_timer2 = 1;
for tester2 = 1:12
if test_timer2 > test_timer1
z = z+ 1;
end
我运行了我在CUDA Python介绍页面上读到的代码:
import numpy as np
from timeit import default_timer as timer
from numbapro import vectorize
@vectorize(["float32(float32, float32)"], target='gpu')
def VectorAdd(a, b):
return a + b
def main():
N = 32000000
A = np.ones(N, dtype=np.float
目前,我在python中遇到了错误,但似乎找不到它们。
def dictionaryObjectParsed():
a = []
b = []
a, b = zip(*(map(lambda x: x.rstrip('\n\r').split('\t'), open('/Users/settingj/Desktop/NOxMultiplier.csv').readlines())))
for x in range(0,len(a)):
print a[x]
print b[x]
d
我需要用Python打印出基于的旋转风扇。
import threading
import subprocess
I = 0
class RepeatingTimer(threading._Timer):
def run(self):
while True:
self.finished.wait(self.interval)
if self.finished.is_set():
return
else:
self.function(
我试图按照基准测试Python、Cython、Numba上给出的示例来计算使用for循环计算的和。不幸的是,我看到Cython比Python慢!
下面是我的Python函数定义:
def python_sum(y):
N = len(y)
x = y[0]
for i in xrange(1,N):
x += y[i]
return x
现在我的Cython函数:
def cython_sum(int[:] y):
cdef int N = y.shape[0]
cdef int x = y[0]
cdef int i
我遇到了一些奇怪的行为,试图对python脚本进行计时。最起码的例子:
foobar.py:
foo = 'Hello'
print(''.join(c for c in foo if c not in 'World'))
print(''.join(c for c in 'World' if c not in foo))
timer.py:
import timeit
timeit.repeat(stmt="exec(open('foobar.py').read())", repe
我正在尝试弄清楚如何让python在一段时间后停止接受输入。 到目前为止,我得到的结果是有效的,但在用户按回车键之前不会停止程序。如果重要的话,我将在Anaconda提示符下运行此文件。 #I've made everything short so it's simpler
def f():
try:
if a != "Accepted word":
timer.cancel
print("...")
quit()
except NameE
我在matlab中创建了一个timeseries数据,它很难描述为一个函数,我想知道将它移植到Python的最佳方法。问题是python中的计时器很少接受数据集的确切值(如果有的话)。我很肯定像这样的东西会起作用:
#this is matlab code just to represent the data
t=linspace(t0,tf,samples);
dataseries;
input=timeseries(dataseries,t);
#python code
def f(timer):
for i in range(0,len(t)):
if timer>t
正如在这个线程Should I use 'has_key()' or 'in' on Python dicts?中提到的,“D.keys()中的键”被认为是O(N),而“D中的键”只是O(1)。 我尝试了下面的测试 from timeit import default_timer as timer
#test if key in D is O(1) but key in D.keys() is O(N)
repeat=100; timer_key={}
for N in [1000, 10000, 100000, 2*10**5, 5*10**5, 1
我试着用python做一个计时器,但是当我运行这段代码时,我被它卡住了。 这是我的代码。 import os
import time
while True:
timer = input("enter the time when to stop the timer = ")
if "second" in timer or "seconds"in timer:
t= timer.replace("second","").replace("seconds","
我为python 2.7.3编写了一个小型python程序:
import time
def fun():
print('Hi')
for i in range(3):
Timer(i, fun).start()
当我运行它时,我会得到错误:
NameError: name 'Timer' is not defined
如何找出哪个模块支持此功能?
我正在用算法和数据进行问题解决的编程练习,structures.The练习是比较lists和字典中del操作符的性能,下面是代码:
import timeit, random
from timeit import Timer
for i in range(1000000, 100000000, 1000000):
x = list(range(i))
t = Timer("del x[random.randrange(%d)]" %i,\
"from __main__ import random,x")
y
我得到了这个错误:
Traceback (most recent call last):
File "D:/Python26/PYTHON-PROGRAMME/049 bam", line 9, in <module>
ball[i][j]=sphere()
NameError: name 'ball' is not defined
当我运行这段代码时。但是球是定义的( balli=sphere() )。不是吗?
#2D-wave
#VPython
from visual import *
#ball array #ready
for
我是python开发的新手,我需要每隔x秒调用一个函数。
因此,我尝试使用计时器来完成此任务,例如:
def start_working_interval():
def timer_tick():
do_some_work() // need to be called on the main thread
timer = threading.Timer(10.0, timer_tick)
timer.start()
timer = threading.Timer(10.0, timer_tick)
timer.star
我正在尝试从一书中学习python,我在第21章中遇到了一些问题,那就是关于python的时间问题。
本书给出了该模块的功能运算时间:
"""
homegrown timing tools for function calls.
Does the total-time, best-of-time, and best of totals time.
"""
import time , sys
timer = time.perf_counter
def total(reps , func , *pargs , **kargs) :
rep