用python对齐数组

Question

我有 3 个文件（file1.txt、file2.txt、file3.txt）看起来像：

文件1：

-7  12
-6  13
-5  11
-4  10
-3  4
-2  8
-1  7
0   9
1   10

文件2：

-5  13
-4  4
-3  5
-2  4
-1  7
0   6
1   9
2   10
3   2

文件3：

-2  3
-1  14
0   8
1   7
2   3
3   9
4   10
5   8
6   3

我想对齐我从这些文件中读取的数组的零点，并获得右侧值的总和，即得到如下内容：

-7  ->  12  + 0  + 0  =  12
-6  ->  13  + 0  + 0  =  13
-5  ->  11  + 13 + 0  =  24
-4  ->  10  + 4  + 0  =  14
-3  ->  4   + 5  + 0  =  9
-2  ->  8   + 4  + 3  =  15
-1  ->  7   + 7  + 14 =  28
0   ->  9   + 6  + 8  =  23
1   ->  10  + 9  + 7  =  26
2   ->  0   + 10 + 3  =  13
3   ->  0   + 2  + 9  =  11
4   ->  0   + 0  + 10 =  10
5   ->  0   + 0  + 8  =  8
6   ->  0   + 0  + 3  =  3
7   ->  0   + 0  + 0  =  0

我怎么能用 Python 做到这一点？提前谢谢你。

Answer 1

只是一个想法，但会有很多：

1. 将所有这些对导入到一个对列表中
2. 创建第二个空对列表
3. 解析第一个列表的每一对并检查该对的第一个元素是否在第二个列表的对的第一个元素中的某个位置。如果它已经是对的第二个元素求和，否则只需将该对附加到第二个列表中。

Answer 2

从开始到结束，假设预期的输出是 csv，并且输入文件是通过“，”分隔的 csv。输出方法非常灵活，但如果有其他预期。

import petl

file1 = petl.fromcsv('file1.csv')
file1 = petl.pushheader(file1, ['position', 'value1'])
file2 = petl.fromcsv('file2.csv')
file2 = petl.pushheader(file2, ['position', 'value2'])
file3 = petl.fromcsv('file3.csv')
file3 = petl.pushheader(file3, ['position', 'value3'])


file1_joined_file2 = petl.outerjoin(file1, file2, key='position')
all_joined = petl.outerjoin(file1_joined_file2, file3, key='position')
all_joined = petl.convert(all_joined, 'value1', {None: 0})
all_joined = petl.convert(all_joined, 'value2', {None: 0})
all_joined = petl.convert(all_joined, 'value3', {None: 0})
all_joined = petl.convert(all_joined, ('position', 'value1', 'value2', 'value3'), int)
all_joined = petl.addfield(all_joined, 'sum', lambda rec: rec['value1'] + rec['value2'] + rec['value3'])
all_joined = petl.sort(all_joined, 'position')

print petl.lookall(all_joined)
petl.tocsv(all_joined, 'done.csv')

上面打印的输出：

+----------+--------+--------+--------+-----+
| position | value1 | value2 | value3 | sum |
+==========+========+========+========+=====+
|       -7 |     12 |      0 |      0 |  12 |
+----------+--------+--------+--------+-----+
|       -6 |     13 |      0 |      0 |  13 |
+----------+--------+--------+--------+-----+
|       -5 |     11 |     13 |      0 |  24 |
+----------+--------+--------+--------+-----+
|       -4 |     10 |      4 |      0 |  14 |
+----------+--------+--------+--------+-----+
|       -3 |      4 |      5 |      0 |   9 |
+----------+--------+--------+--------+-----+
|       -2 |      8 |      4 |      3 |  15 |
+----------+--------+--------+--------+-----+
|       -1 |      7 |      7 |     14 |  28 |
+----------+--------+--------+--------+-----+
|        0 |      9 |      6 |      8 |  23 |
+----------+--------+--------+--------+-----+
|        1 |     10 |      9 |      7 |  26 |
+----------+--------+--------+--------+-----+
|        2 |      0 |     10 |      3 |  13 |
+----------+--------+--------+--------+-----+
|        3 |      0 |      2 |      9 |  11 |
+----------+--------+--------+--------+-----+
|        4 |      0 |      0 |     10 |  10 |
+----------+--------+--------+--------+-----+
|        5 |      0 |      0 |      8 |   8 |
+----------+--------+--------+--------+-----+
|        6 |      0 |      0 |      3 |   3 |
+----------+--------+--------+--------+-----+