减少 Python 中的循环是不可能的？
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Decreasing for loops in Python impossible?
提问by Gal
I could be wrong (just let me know and I'll delete the question) but it seems python won't respond to
我可能是错的（请告诉我，我会删除问题）但似乎 python 不会响应
for n in range(6,0):
print n
I tried using xrange and it didn't work either. How can I implement that?
我尝试使用 xrange 但它也不起作用。我该如何实施？
采纳答案by Steve Tjoa
for n in range(6,0,-1):
print n
# prints [6, 5, 4, 3, 2, 1]
回答by cji
for n in range(6,0,-1):
print n
回答by vanza
>>> range(6, 0, -1)
[6, 5, 4, 3, 2, 1]
回答by pratikm
This is very late, but I just wanted to add that there is a more elegant way: using reversed
这已经很晚了，但我只想补充一点，有一种更优雅的方式：使用 reversed
for i in reversed(range(10)):
print i
gives:
给出：
4
3
2
1
0
回答by Handy Jodana
for n in range(6,0,-1)
This would give you 6,5,4,3,2,1
这会给你 6,5,4,3,2,1
As for
至于
for n in reversed(range(0,6))
would give you 5,4,3,2,1,0
会给你 5,4,3,2,1,0
回答by Neo
0 is conditional value when this condition is true, loop will keep executing.10 is the initial value. 1 is the modifier where may be simple decrement.
0 为条件值，当此条件为真时，循环将继续执行。10 为初始值。1 是修饰符，可能是简单的递减。
for number in reversed(range(0,10,1)):
print number;
回答by Mark Moretto
Late to the party, but for anyone tasked with creating their own or wants to see how this would work, here's the function with an added bonus of rearranging the start-stop values based on the desired increment:
晚会晚了，但对于任何负责创建自己的任务或想看看这将如何工作的人来说，这里有一个额外的好处，即根据所需的增量重新排列开始-停止值：
def RANGE(start, stop=None, increment=1):
if stop is None:
stop = start
start = 1
value_list = sorted([start, stop])
if increment == 0:
print('Error! Please enter nonzero increment value!')
else:
value_list = sorted([start, stop])
if increment < 0:
start = value_list[1]
stop = value_list[0]
while start >= stop:
worker = start
start += increment
yield worker
else:
start = value_list[0]
stop = value_list[1]
while start < stop:
worker = start
start += increment
yield worker
Negative increment:
负增量：
for i in RANGE(1, 10, -1):
print(i)
Or, with start-stop reversed:
或者，起止颠倒：
for i in RANGE(10, 1, -1):
print(i)
Output:
输出：
10
9
8
7
6
5
4
3
2
1
Regular increment:
常规增量：
for i in RANGE(1, 10):
print(i)
Output:
输出：
1
2
3
4
5
6
7
8
9
Zero increment:
零增量：
for i in RANGE(1, 10, 0):
print(i)
Output:
输出：
'Error! Please enter nonzero increment value!'
回答by SREERAG R NANDAN
For python3 where -1indicate the value that to be decremented in each step
for n in range(6,0,-1):
print(n)
对于python3，其中-1指示在每一步中要递减的值
for n in range(6,0,-1):
print(n)
