简单HTTP服务器

python -m SimpleHTTPServer 8080

Python中字符与数字转换

ASCII值与字符的转换：

>>> chr(65), ord('A')
('A', 65)

不同进制的字符串

>>> bin(15), oct(15), hex(15)
('0b1111', '017', '0xf')
>>> int('1111',2), int('17',8), int('f',16)
(15, 15, 15) 

python时间

import time

start = time.monotonic()
time.sleep(0.2)
end = time.monotonic()

print("start: {:>9.2f}".format(start))
print("end: {:>9.2f}".format(end))
print("span: {:>9.2f}".format(end - start))

start = time.perf_counter()
i = 0
while i < 100000:
    i = i + 1

elapsed_time = time.perf_counter() - start
print("Elapsed time: {}".format(elapsed_time))

Python调用C模块

C源代码：

#include <stdio.h>

int sum(int a, int b) {
	return a + b;
}

编译C源代码为so库文件：

gcc -fPIC -shared sample.c -o sample.so

Python代码中调用ctype模块加载so文件：

import sys
from ctypes import *    # load ctype module

c_object = CDLL('./sample.so')
print(c_object.sum(3, 40))

测试执行效果：

python3 sample.py             # show: 43