将Python列表分成5组，然后打印

Question

I have a list item that looks like this:

dblist=['one', 'two', 'three', 'four', 'five', 'six', 'seven', 'eight', 'nine', 'ten', 'eleven', 'twelve']

It could have more than 12 items (could be infinite). I want to print this list in groups of five and want my output to look like this:

env1: one two three four five
env2: six seven eight nine ten
env3: eleven twelve

How can I achieve this?

I found some nice tricks that appear to be able to do the job, but I just can't seem to make it work with my code. For example, the following seems to be able to do what I want:

def n_split(iterable, n, fillvalue=None):
    num_extra = len(iterable) % n
    zipped = zip(*[iter(iterable)] * n)
    return zipped if not num_extra else zipped + [iterable[-num_extra:], ]

for ints in n_split(range(1,32), 5):
    print(([str(i) for i in ints]))

Has the output of:

['1', '2', '3', '4', '5']
['6', '7', '8', '9', '10']
['11', '12', '13', '14', '15']
['16', '17', '18', '19', '20']
['21', '22', '23', '24', '25']
['26', '27', '28', '29', '30']
['31', '32', '33']

How can I use this technique to print dblist in groups of five as shown in the beginning?

Answer 1

Use str.join() :

for group in n_split(dblist, 5):
    print ' '.join(group)

You could add enumerate() to add a counter:

for count, group in enumerate(n_split(dblist, 5), 1):
    print 'env{}: {}'.format(count, ' '.join(group))

Demo:

>>> def n_split(iterable, n, fillvalue=None):
...     num_extra = len(iterable) % n
...     zipped = zip(*[iter(iterable)] * n)
...     return zipped if not num_extra else zipped + [iterable[-num_extra:], ]
... 
>>> dblist=['one', 'two', 'three', 'four', 'five', 'six', 'seven', 'eight', 'nine', 'ten', 'eleven', 'twelve']
>>> for group in n_split(dblist, 5):
...     print ' '.join(group)
... 
one two three four five
six seven eight nine ten
eleven twelve
>>> for count, group in enumerate(n_split(dblist, 5), 1):
...     print 'env{}: {}'.format(count, ' '.join(group))
... 
env1: one two three four five
env2: six seven eight nine ten
env3: eleven twelve

Answer 2

Is this what you want?

dblist=['one', 'two', 'three', 'four', 'five', 'six', 'seven', 'eight', 'nine', 'ten', 'eleven', 'twelve']
for i in range(0,len(dblist),5):
    print(dblist[i:i+5])

['one', 'two', 'three', 'four', 'five']
['six', 'seven', 'eight', 'nine', 'ten']
['eleven', 'twelve']