我是python的新手,这是我编写的第一个代码。试图使用NLTK包。在尝试执行label_probdist.prob(' positive')行时,问题就出现了。 这是我得到的错误;
name 'label_probdist' is not defined
NameError Traceback (most recent call last)
<ipython-input-57-006d791d4445> in <module>()
----> 1 print label_probdist.prob('positive')
NameError: name 'label_probdist' is not defined
import nltk, re, pprint
import csv
from nltk import word_tokenize, wordpunct_tokenize
from nltk.tokenize import wordpunct_tokenize
from nltk.probability import FreqDist, DictionaryProbDist, ELEProbDist, sum_logs
from nltk.classify.api import ClassifierI
# not in use nltk.download() #Download the bookpackage
#open the file that containts wallposts and classifier
with open('Classified.csv' ,'rb') as f:
reader = csv.reader(f)
FBsocial = map(tuple, reader)
import random
random.shuffle(FBsocial)
FBsocial = FBsocial[:500]
len(FBsocial)
FBSocialData = [] #sorting data
for row in FBsocial:
statement = row[0]
sentiment = row[1]
words_filtered = [e.lower() for e in statement.split() if len(e) >= 3]
FBSocialData.append((words_filtered, sentiment))
len(FBSocialData)
#Extracting features of word(list of words ordered by frequency)
def get_words_in_FBdata(FBSocialData):
all_words = []
for (statement, sentiment) in FBSocialData:
all_words.extend(statement)
return all_words
def get_word_features(wordlist):
wordlist = nltk.FreqDist(wordlist)
word_features = wordlist.keys()
return word_features
word_features = get_word_features(get_words_in_FBdata(FBSocialData))
len(word_features)
#just a test;
document = ("hei","grin","andre","jævlig","gøy",)
#Classifier to decide which feature are relevant
def extract_features(document):
document_words = set(document)
features = {}
for word in word_features:
features['contains(%s)' % word] = (word in document_words)
return features
extract_features(document)
#testing extract_features
extract_features("udviser blomsterbutik")
training_set = nltk.classify.util.apply_features(extract_features, FBSocialData)
len(training_set)
classifier = nltk.NaiveBayesClassifier.train(training_set)
def train(labeled_featuresets, estimator=nltk.probability.ELEProbDist):
# Create the P(label) distribution
label_probdist = estimator(label_freqdist)
# Create the P(fval|label, fname) distribution
feature_probdist = {}
return NaiveBayesClassifier(label_probdist, feature_probdist)
#pvalue
print label_probdist.prob('positive')
print label_probdist.prob('negative')
答案 0 :(得分:1)
您正在功能列车中定义变量label_probdist
。然后你试图在它的范围之外访问它。这不可能。它是一个局部变量,而不是全局变量。