x.strip() for x in f.read().strip().splitlines() if len(x.strip())
时间: 2023-10-06 08:14:25 浏览: 54
这行代码的作用是从文件对象f中读取内容,去除每行两端的空白字符,并将非空行添加到列表中。具体来说,它的实现步骤如下:
1. `f.read()`:读取文件对象f的全部内容,返回一个字符串。
2. `strip()`:去除字符串两端的空白字符(包括空格、制表符、换行符等),返回一个新的字符串。
3. `splitlines()`:将字符串按行分割,返回一个包含每行内容的列表。
4. `x.strip() for x in ...`:对列表中的每个元素(即每行内容)执行strip()操作,返回一个新的包含处理后内容的列表。
5. `if len(x.strip())`:判断处理后的每行内容是否为空,如果不为空则保留该行内容,否则丢弃。
最终,这行代码将返回一个列表,其中包含了去除了空白字符和空行的文件内容。
相关问题
注释这段代码 def __init__(self, sources='streams.txt', img_size=640, stride=32): self.mode = 'stream' self.img_size = img_size self.stride = stride if os.path.isfile(sources): with open(sources, 'r') as f: sources = [x.strip() for x in f.read().strip().splitlines() if len(x.strip())] else: sources = [sources] n = len(sources) self.imgs = [None] * n self.sources = [clean_str(x) for x in sources] # clean source names for later
这是一个Python类的初始化函数,用于初始化类的属性。它接受三个参数:sources、img_size和stride。
1. sources参数表示输入的视频流文件名或者文件名列表。如果传入的是文件名,则读取文件内容,将每一行的空白字符去除后作为视频流文件名列表。如果传入的是文件名列表,则直接使用该列表。
2. img_size参数表示输入视频的大小,它的默认值为640。
3. stride参数表示步长,它的默认值为32。
在初始化方法中,还对传入的视频流文件名进行了清理,将其存储在self.sources列表中。
最后,还初始化了self.mode属性为'stream',self.imgs属性为长度为n的None列表。
给以下这段代码加上结果可视化的功能:from sklearn.feature_extraction.text import CountVectorizer from sklearn.naive_bayes import MultinomialNB import jieba from sklearn.model_selection import train_test_split import numpy as np import matplotlib.pyplot as plt good_comments = [] bad_comments = [] with open('D:\PyCharmProjects\爬虫测试\好评.txt', 'r', encoding='gbk') as f: for line in f.readlines(): good_comments.append(line.strip('\n')) with open('D:\PyCharmProjects\爬虫测试\差评.txt', 'r', encoding='gbk') as f: for line in f.readlines(): bad_comments.append(line.strip('\n')) with open('StopWords.txt', 'r', encoding='utf-8') as f: stopwords = f.read().splitlines() good_words = [] for line in good_comments: words = jieba.cut(line, cut_all=False) words = [w for w in words if w not in stopwords] good_words.append(' '.join(words)) bad_words = [] for line in bad_comments: words = jieba.cut(line, cut_all=False) words = [w for w in words if w not in stopwords] bad_words.append(' '.join(words)) # 将文本转换为向量 vectorizer = CountVectorizer() X = vectorizer.fit_transform(good_words + bad_words) y = [1] * len(good_words) + [0] * len(bad_words) # 将数据分为训练集和测试集 X_train, X_test, y_train, y_test = train_test_split(X, y, test_size=0.2) # 训练模型 clf = MultinomialNB() clf.fit(X_train, y_train) # 测试模型并计算准确率 pred = clf.predict(X_test) accuracy = sum(pred == y_test) / len(y_test) print('准确率:{:.2%}'.format(accuracy)) # 预测新数据的类别 with open('测试评论.txt', 'r', encoding='utf-8') as f: count = 0 for line in f.readlines(): count += 1 test_text = line.strip('\n') test_words = ' '.join(jieba.cut(test_text, cut_all=False)) test_vec = vectorizer.transform([test_words]) pred = clf.predict(test_vec) if pred[0] == 1: print(count, '好评') else: print(count, '差评')
以下是加上结果可视化的代码:
```
from sklearn.feature_extraction.text import CountVectorizer
from sklearn.naive_bayes import MultinomialNB
import jieba
from sklearn.model_selection import train_test_split
import numpy as np
import matplotlib.pyplot as plt
good_comments = []
bad_comments = []
# 读取好评和差评文本
with open('D:\PyCharmProjects\爬虫测试\好评.txt', 'r', encoding='gbk') as f:
for line in f.readlines():
good_comments.append(line.strip('\n'))
with open('D:\PyCharmProjects\爬虫测试\差评.txt', 'r', encoding='gbk') as f:
for line in f.readlines():
bad_comments.append(line.strip('\n'))
with open('StopWords.txt', 'r', encoding='utf-8') as f:
stopwords = f.read().splitlines()
# 对好评和差评文本进行分词和去除停用词
good_words = []
for line in good_comments:
words = jieba.cut(line, cut_all=False)
words = [w for w in words if w not in stopwords]
good_words.append(' '.join(words))
bad_words = []
for line in bad_comments:
words = jieba.cut(line, cut_all=False)
words = [w for w in words if w not in stopwords]
bad_words.append(' '.join(words))
# 将文本转换为向量
vectorizer = CountVectorizer()
X = vectorizer.fit_transform(good_words + bad_words)
y = [1] * len(good_words) + [0] * len(bad_words)
# 将数据分为训练集和测试集
X_train, X_test, y_train, y_test = train_test_split(X, y, test_size=0.2)
# 训练模型
clf = MultinomialNB()
clf.fit(X_train, y_train)
# 测试模型并计算准确率
pred = clf.predict(X_test)
accuracy = sum(pred == y_test) / len(y_test)
print('准确率:{:.2%}'.format(accuracy))
# 可视化结果
fig, ax = plt.subplots()
ax.bar(['差评', '好评'], [len(bad_comments), len(good_comments)], color=['red', 'green'])
ax.set_xlabel('评论类型')
ax.set_ylabel('评论数量')
ax.set_title('评论数量统计')
plt.show()
# 预测新数据的类别
with open('测试评论.txt', 'r', encoding='utf-8') as f:
count = 0
for line in f.readlines():
count += 1
test_text = line.strip('\n')
test_words = ' '.join(jieba.cut(test_text, cut_all=False))
test_vec = vectorizer.transform([test_words])
pred = clf.predict(test_vec)
if pred[0] == 1:
print(count, '好评')
else:
print(count, '差评')
```
运行以上代码后,会得到一个柱状图,用于展示好评和差评的数量统计。同时,在预测新数据的类别时,也会在控制台输出每一条评论的分类结果。
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