用python制作索引

Question

以下是我的问题:

data = ['a1_1 00000001\n', 'a1_2 00000002\n', 'a1_3 00000003\n',
        'b1_1 00000004\n', 'b1_2 00000005\n', 'b1_3 00000006']

candidate = ['a', 'b']

for i in candidate:
    for j in data:
        if i in j.split()[0]:
            print i, j.split()[1]

a 00000001
a 00000002
a 00000003
b 00000004
b 00000005
b 00000006

但我想要做的是如下结果:

a 00000001, 00000002, 00000003
b 00000004, 00000005, 00000006

我该如何解决这个问题？提前致谢!

Answer 1

data = ['a1_1 00000001\n', 'a1_2 00000002\n', 'a1_3 00000003\n', 'b1_1 00000004\n', 'b1_2 00000005\n', 'b1_3 00000006']

candidate = ['a', 'b']


for i in candidate:
    print i, ', '.join(v for k,v in (a.split() for a in data) if k.startswith(i))

打印:

a 00000001, 00000002, 00000003
b 00000004, 00000005, 00000006

然而,这将经历data几次(每次一次candidate).要做一次,你需要一个中间词典:

d = {}
for a in data:
    d.setdefault(a[0], []).append(a.split()[1])
for k,v in sorted(d.iteritems()):
    print k, ', '.join(v)