python - 写入列表到具有特定列数的行

Question

我正在尝试将列表写入具有特定列数的行。例如，取列表:

data = [1.0, 2.0, 3.0, 4.0, 5.0, 6.0, 7.0, 8.0, 9.0, 10.0]

我想用这样的格式写出来:

 1.0,  2.0,  3.0,
 4.0,  5.0,  6.0,
 7.0,  8.0,  9.0,
10.0,

我试过下面的代码；但是，只能让它打印第一行:

strformat = ['{'+str(i)+':>5.1f},' for i in range(0,3)]
strformat = ''.join(strformat).lstrip().rstrip() + '\n'
print strformat.format(*[x for x in data])

提前致谢!

Answer 1

def chunks(seq, n):
    # http://stackoverflow.com/a/312464/190597 (Ned Batchelder)
    """ Yield successive n-sized chunks from seq."""
    for i in xrange(0, len(seq), n):
        yield seq[i:i + n]

data = [1.0, 2.0, 3.0, 4.0, 5.0, 6.0, 7.0, 8.0, 9.0, 10.0]
for row in chunks(data, 3):
    print(',  '.join(map(str, row)))

产量

1.0,  2.0,  3.0
4.0,  5.0,  6.0
7.0,  8.0,  9.0
10.0

或者，也许更接近您的代码:

strformat = '\n'.join(
    ',  '.join('{:>5.1f}' for item in row) 
    for row in chunks(data, 3))
print(strformat.format(*data))