Decreasing for loops in Python impossible?

I could be wrong (just let me know and I'll delete the question) but it seems python won't respond to

for n in range(6,0): print n 

I tried using xrange and it didn't work either. How can I implement that?

8 Answers

for n in range(6,0,-1): print n # prints [6, 5, 4, 3, 2, 1] 

This is very late, but I just wanted to add that there is a more elegant way: using reversed

for i in reversed(range(10)): print i 

gives:

4 3 2 1 0 

for n in range(6,0,-1) 

This would give you 6,5,4,3,2,1

As for

for n in reversed(range(0,6)) 

would give you 5,4,3,2,1,0

for n in range(6,0,-1): print n 

>>> range(6, 0, -1) [6, 5, 4, 3, 2, 1] 

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.

for number in reversed(range(0,10,1)): print number; 

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:

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:

for i in RANGE(1, 10, -1): print(i) 

Or, with start-stop reversed:

for i in RANGE(10, 1, -1): print(i) 

Output:

10 9 8 7 6 5 4 3 2 1 

Regular increment:

for i in RANGE(1, 10): print(i) 

Output:

1 2 3 4 5 6 7 8 9 

Zero increment:

for i in RANGE(1, 10, 0): print(i) 

Output:

'Error! Please enter nonzero increment value!' 

For python3 where -1 indicate the value that to be decremented in each step for n in range(6,0,-1): print(n)