正在表达式初练---摄氏单位和华氏单位转换
精通正则表达式中，有一个温度转换程序，使用perl写的，现在转换成python来写，也算是对re的一个应用：
#!/usr/bin/env python
#-*- coding: utf-8 -*-
#filename:temperature_exchange.py
import re
def Match():
imply = raw_input("Type you temperature(e.g:32F,100C): ")
re_str = r'([-+]?[0-9]+(\.[0-9]*)?)\s*([CF])$'
match = re.match(re_str,imply,re.I)
if match:
num = re.search(re_str,imply,re.I).group(1)
kind = re.search(re_str,imply,re.I).group(3)
if(kind == 'c' or kind == 'C'):
c = float(num)
f = (c * 9 / 5) + 32
else:
f = float(num)
c = (f - 32) * 5 / 9
print "%.2fC is equal to %.2fF \n" % (c,f)
else:
print "\nExpecting a number followed by C or F "
print "sorry,your type style is out of the regular!\n"
while True:
Match() 运行测试情况如下：
>>> ================================ RESTART ================================ >>> Type you temperature(e.g:32F,100C): 23f -5.00C is equal to 23.00F Type you temperature(e.g:32F,100C): 45F 7.22C is equal to 45.00F Type you temperature(e.g:32F,100C): 34c 34.00C is equal to 93.20F Type you temperature(e.g:32F,100C): 23C 23.00C is equal to 73.40F Type you temperature(e.g:32F,100C): 23 Expecting a number followed by C or F sorry,your type style is out of the regular! Type you temperature(e.g:32F,100C): 23.4 Expecting a number followed by C or F sorry,your type style is out of the regular! Type you temperature(e.g:32F,100C): 23.45F] Expecting a number followed by C or F sorry,your type style is out of the regular! Type you temperature(e.g:32F,100C): 23.45F -4.75C is equal to 23.45F Type you temperature(e.g:32F,100C): -23 Expecting a number followed by C or F sorry,your type style is out of the regular! Type you temperature(e.g:32F,100C): -23F -30.56C is equal to -23.00F Type you temperature(e.g:32F,100C): -23C -23.00C is equal to -9.40F Type you temperature(e.g:32F,100C): +45F 7.22C is equal to 45.00F Type you temperature(e.g:32F,100C): +34.45f 1.36C is equal to 34.45F