我尝试在python中尝试mapreduce pairs模式。需要检查一个单词是否在文本文件中,然后找到它旁边的单词并生成两个单词对。继续遇到:
neighbors = words[words.index(w) + 1]
ValueError: substring not found
或者
^{pr2}$文件工作_试用版.py在
from mrjob.job import MRJob
class MRCountest(MRJob):
# Word count
def mapper(self, _, document):
# Assume document is a list of words.
#words = []
words = document.strip()
w = "the"
neighbors = words.index(w)
for word in words:
#searchword = "the"
#wor.append(str(word))
#neighbors = words[words.index(w) + 1]
yield(w,1)
def reducer(self, w, values):
yield(w,sum(values))
if __name__ == '__main__':
MRCountest.run()
编辑: 尝试使用pairs模式在文档中搜索特定单词的每个实例,然后每次都找到它旁边的单词。然后为每个实例生成一对结果,即查找“the”的实例及其旁边的单词,即[the]、[book]、[the]、[cat]等
from mrjob.job import MRJob
class MRCountest(MRJob):
# Word count
def mapper(self, _, document):
# Assume document is a list of words.
#words = []
words = document.split(" ")
want = "the"
for w, want in enumerate(words, 1):
if (w+1) < len(words):
neighbors = words[w + 1]
pair = (want, neighbors)
for u in neighbors:
if want is "the":
#pair = (want, neighbors)
yield(pair),1
#neighbors = words.index(w)
#for word in words:
#searchword = "the"
#wor.append(str(word))
#neighbors = words[words.index(w) + 1]
#yield(w,1)
#def reducer(self, w, values):
#yield(w,sum(values))
if __name__ == '__main__':
MRCountest.run()
就目前的情况来看,我得到了每一个词对的产出率是同一对的倍数。在
当您使用
words.index("the")
时,您将只得到列表或字符串中“the”的第一个实例,正如您所发现的那样,如果“the”不存在,您将得到一个错误。在你还提到你正在尝试产生对,但只产生一个单词。在
我想你想做的是这样:
假设你对两个方向的邻居都感兴趣。(如果没有,你只需要第一个收益。)
最后,由于您使用
document.strip()
,我怀疑文档实际上是一个字符串而不是一个列表。如果是这样的话,可以使用words = document.split(" ")
来获取单词列表,假设没有标点符号。在相关问题 更多 >
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