Python:csv outpu中的数据不匹配

2024-09-25 16:23:08 发布

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假设我有两个csv输出,如下所示:

mark1 :

[['a', '', '', '', '', ''], ['b', '', '', '', '', ''], ['c', '', '', '', '', ''], ['d', '', '', '', '', ''], ['e', '', '', '', '', ''], ['f', '', '', '', '', ''], ['g', '', '', '', '', '']]

以及

mark2:

[['a', '10', '', '', '', ''], ['b', '', '', '', '', ''], ['c', '10', '', '', '', ''], ['d', '', '', '', '', ''], ['e', '7', '', '', '', ''], ['m', '9', '', '', '', ''], ['n', '', '', '', '', '']]

在这种情况下,在第一个csv输出中找不到m和n。 所以我写的代码是:

mark1[row][0] != mark2[row1][0]:

            print 'some marks are not the same - no match found'

上面的代码不起作用。你知道吗

有什么具体的办法解决这个问题吗?你知道吗

谢谢。你知道吗


Tags: csvtheno代码not情况someare
3条回答

如果要比较整个列表,则应比较它们:

 if mark1 != mark2:
      print 'some are not the same...'

如果您只想比较列表中每个列表的第一个字段,这是一种方法。你知道吗

def compare_first(mark1,mark2):
  for row in mark1:
    for row2 in mark2:
      if row[0] != row2[0]:
        return false;
  return true

然后主要使用这个函数

if !equal_firs(mark1,mark2):
  print('some are not the same...')

我发现最简单(计算速度最快)的方法是这样做:

if [n for n in mark2 if n[0] not in [m[0] for m in mark1]]:
    print 'some marks are not found...'

需要两个for循环来比较每个要迭代的值。上面的代码大致翻译为:

keys = []
for m in mark1:
    keys.append(m[0])
for n in mark2:
    if n not in keys:
        print 'some marks not found...'
        break

我先说我投票支持@ThaneBrimhall的答案,但是为了展示各种方式(假设你只关心一个元素是否在另一个元素中,而不管其位置如何):

# Get a set of unique first elements for each list
set1 = set([n[0] for n in mark1])
set2 = set([n[0] for n in mark2])

# Items in mark1 but not mark2
if set1.difference(set2):
  print 'some marks are not the same - no match found'

# Items in mark2 but not mark1
if set2.difference(set1):
  print 'some marks are not the same - no match found'

如果你想知道是什么导致了错误:

# Get a set of unique first elements for each list
set1 = set([n[0] for n in mark1])
set2 = set([n[0] for n in mark2])

# Items in mark1 but not mark2
set1_diffs = set1.difference(set2)
if set1_diffs:
  print 'Marks {0} in mark1 but not mark2'.format(list(set1_diffs))

# Items in mark2 but not mark1
set2_diffs = set2.difference(set1)
if set2_diffs:
  print 'Marks {0} in mark2 but not mark1'.format(list(set2_diffs))

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