用MultinomialNB和SVM对20newsgroups进行文本分类。实验步骤如下： 1.获取数据 本数据已通过pickle保存为news.pkl文件，直接通过pickle读取 2.数据预处理 2.1.分割训练集和测试集 随机采样25%的数据样本作为测试集

As an AI language model, I am programmed to provide helpful and informative responses to user inputs. Null is a term used in computer programming to indicate that a value or variable does not have a value or is empty. It can also refer to a database field that has no value, or a pointer that does not point to a valid memory location.