“NoneType”类型的对象没有len(),但我很确定我的对象是有效列表

时间:2012-07-10 20:25:45

标签: python list

以下模块对我来说失败了,告诉我'NoneType'类型的对象没有len(),但似乎传递的对象是一个列表,而不是'NoneType'类型的对象。我在下面包含了模块和输出。

def Purge_Polyploid_MisScores(dictOfLists):
  #print "dict getting passed to Purge_Polyploid_MisScores function", dictOfLists
  for x in dictOfLists.keys():
    for y in range (0, len(dictOfLists[x])):
      print "x", x, " and y", y
      print dictOfLists[x][y]
      #if not dictOfLists[x][y]:
        #print "error at ",x,dictOfLists[str(int(x)-1)][0]
      if len(dictOfLists[x][y])>3:
        try:
          dictOfLists[x][y]=dictOfLists[x][y].remove('**')
        except:
          for z in dictOfLists[x][y]:
            if dictOfLists[x][y].count(z)>2:
              print "removed ",z," at dictOfLists[",x,"][",y,"]", dictOfLists[x][y]
              dictOfLists[x][y].remove(z)
              #I think this produces an error: dictOfLists[x][y]=dictOfLists[x][y].remove(z)
              print "now, it looks like", dictOfLists[x][y]
        if len(dictOfLists[x][y])>3:
          print "The Length is still greater than 3! at dictOfLists[",x,"][",y,"]", dictOfLists[x][y]

          #print "the reason you have a polyploid is not a mis-score"
          #print "dictOfLists[",x,"][",y,"]",dictOfLists[x][y]
      print "Reached the end of the loop"
  return dictOfLists

错误之前的错误/输出:

x 449  and y 100
['Yellow submarine', '273', '273']
Reached the end of the loop
x 449  and y 101
['Heartland', '250', '250', '250']
removed  250  at dictOfLists[ 449 ][ 101 ] ['Heartland', '250', '250', '250']
now, it looks like ['Heartland', '250', '250']
Reached the end of the loop
x 449  and y 102
['Julia', '116', '119', '**']
Traceback (most recent call last):
  File "fast_run.py", line 11, in <module>
    sample_names_list_e1_keys_as_numbers_e2=transpose.combine_allele_report_pipeline_dict(pipeline_directory, keeplist_address, rejected_samples_address)
  File "/Users/markfisher/transpose.py", line 887, in combine_allele_report_pipeline_dict
    samples=Purge_Polyploid_MisScores(samples)
  File "/Users/markfisher/transpose.py", line 1332, in Purge_Polyploid_MisScores
    if len(dictOfLists[x][y])>3:
TypeError: object of type 'NoneType' has no len() 

换句话说,如果['Julia', '116', '119', '**']len(['Julia', '116', '119', '**'])>3似乎失败了,我不明白为什么。

我希望我能让你们有足够的能力看到我的错误!谢谢!

2 个答案:

答案 0 :(得分:10)

问题在于:dictOfLists[x][y]=dictOfLists[x][y].remove('**')remove列表方法会删除元素就地,改变原始列表,并返回None,因此您将列表设置为None。相反,只需dictOfLists[x][y].remove('**')

答案 1 :(得分:1)

@BrenBarn得到了正确答案,我知道这应该是评论,而不是答案;但是我不能在评论中发布代码。

如果你的循环中你有dictOfLists[x][y]九次,那么结构上就会出现问题。

  • 使用items()获取键和值,而不仅仅是键,然后查找值
  • 使用enumerate获取列表中的索引和值,而不是迭代range(len(

更像是:

def Purge_Polyploid_MisScores(dictOfLists):
    for key,lst in dictOfLists.items():
        for i,val in enumerate(lst):
                print "key: %s index: %i val: %s"%(key,i,val)
                if len(val)>3:
                    val.remove('**')

对不起,如果重写冒犯,但你考虑发布测试代码(+1),所以我想让你建设性(希望)反馈回报