计算程序运行时间的6种方法

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#方法1
import time
def test():
start_time = time.time()
# 记录程序开始运行时间
s = 0
for i in range(1000000):
s += 1
end_time = time.time()
# 记录程序结束运行时间
print('Took %f second' % (end_time - start_time))
return s
test()
#方法2
import datetime
s=0
starttime = datetime.datetime.now()
#long running
for i in range(1000000):
s += 1
endtime = datetime.datetime.now()
print (endtime - starttime)
#方法3：
from time import process_time
process_time()
for i in range(1000000):
s += 1
print("运行时间是: {:9.9}s".format(process_time()))
#方法4
#import time
def func(s):
print('func start')
for i in range(1000000):
s += 1
print('func end')
t = time.time()
func(0)
print(f'时间差:{time.time() - t:.3f}s')
#方法5
#import time
import timeit
def func():
s=0
#print('func start')
for i in range(1000000):
s += 1
#print('func end')
#return s
print(timeit.timeit(stmt=func, number=1))
'''
运行结果：
Took 0.054998 second
0:00:00.106030
运行时间是:
1.015625s
func start
func end
时间差:0.056s
0.05572290000000002
'''
#方法6
#测量小代码段的执行时间
import timeit
t = timeit.Timer('li = list(map(lambda x:x*2,[1,2,3,4,5]))')
print(t.timeit())
print(t.repeat())
'''
显示结果
0.8614424
[0.8119543999999999, 0.8170989999999998, 0.8176573, 0.8120596999999998, 0.8147238999999997]
'''
#引号中的程序运行结果：
li = list(map(lambda x:x*2,[1,2,3,4,5]))
print(li)
#显示结果：[2, 4, 6, 8, 10]