我正在尝试向我的程序添加一个选项,该选项允许用户选择他想要执行的程序的哪些步骤。
我希望能够解析一个字符串,比如"1-3,6,8-10"
和 get [1, 2, 3, 6, 8, 9, 10]
。
你知道 Python 中正在做的事情是否已经存在吗?
我正在尝试向我的程序添加一个选项,该选项允许用户选择他想要执行的程序的哪些步骤。
我希望能够解析一个字符串,比如"1-3,6,8-10"
和 get [1, 2, 3, 6, 8, 9, 10]
。
你知道 Python 中正在做的事情是否已经存在吗?
此功能可以满足您的要求。它假定没有使用负数,否则需要进行一些更改来支持这种情况。
def mixrange(s):
r = []
for i in s.split(','):
if '-' not in i:
r.append(int(i))
else:
l,h = map(int, i.split('-'))
r+= range(l,h+1)
return r
print mixrange('1-3,6,8-10')
使用列表推导的一种方法:
s = "1-3,6,8-10"
x = [ss.split('-') for ss in s.split(',')]
x = [range(int(i[0]),int(i[1])+1) if len(i) == 2 else i for i in x]
print([int(item) for sublist in x for item in sublist])
输出:
[1, 2, 3, 6, 8, 9, 10]
没有内置函数,但可以使用xrange
和生成器完成:
from itertools import chain
s = "1-3,6,8-10"
spans = (el.partition('-')[::2] for el in s.split(','))
ranges = (xrange(int(s), int(e) + 1 if e else int(s) + 1) for s, e in spans)
all_nums = chain.from_iterable(ranges) # loop over, or materialse using `list`
# [1, 2, 3, 6, 8, 9, 10]
我刚刚创建的一个小函数:
def expand(st):
res = []
for item in st.split(','):
if '-' in item:
temp = map(int, item.split('-'))
res.extend(range(temp[0], temp[1]+1))
else:
res.append(int(item))
return res
s = '1-3,6,8-10'
print expand(s)
回报:
[1, 2, 3, 6, 8, 9, 10]
s = '1-3,6,8-10,13-16'
temp = [x.split('-') if '-' in x else x for x in s.split(',')]
# temp = [['1', '3'], '6', ['8', '10'], ['13', '16']]
res = []
for l in temp:
if isinstance(l, list):
a, b = map(int, l)
res += list(range(a, b + 1))
else:
res.append(int(l))
# res = [1, 2, 3, 6, 8, 9, 10, 13, 14, 15, 16]
def parseIntSet(nputstr=""):
selection = set()
invalid = set()
# tokens are comma seperated values
tokens = [x.strip() for x in nputstr.split(',')]
for i in tokens:
try:
# typically tokens are plain old integers
selection.add(int(i))
except:
# if not, then it might be a range
try:
token = [int(k.strip()) for k in i.split('-')]
if len(token) > 1:
token.sort()
# we have items seperated by a dash
# try to build a valid range
first = token[0]
last = token[len(token)-1]
for x in range(first, last+1):
selection.add(x)
except:
# not an int and not a range...
invalid.add(i)
# Report invalid tokens before returning valid selection
print "Invalid set: " + str(invalid)
return selection
啊哈,任何人的概念证明?
编辑:改进版
import itertools
s = "1-3,6,8-10"
print(list(itertools.chain.from_iterable(range(int(ranges[0]), int(ranges[1])+1) for ranges in ((el+[el[0]])[:2] for el in (miniRange.split('-') for miniRange in s.split(','))))))
现在分成几行以提高可读性:
print(list(itertools.chain.from_iterable(
range(
int(ranges[0]),
int(ranges[1])+1
)
for ranges in
(
(el+[el[0]])[:2] # Allows to get rid of the ternary condition by always adding a duplicate of the first element if it is alone
for el in
(miniRange.split('-') for miniRange in s.split(','))
)
)))