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python中带[]的for循环做什么?_Python_Loops_Csv - Fatal编程技术网

python中带[]的for循环做什么?

python中带[]的for循环做什么?,python,loops,csv,Python,Loops,Csv,下面的代码片段有一个for循环,在[]括号内有csv文件名 TRAIN_CSV = './train1.csv' # this comtains 100 entries TEST_CSV = './test1.csv' # this contains 50 entries train_df = pd.read_csv(TRAIN_CSV) test_df = pd.read_csv(TEST_CSV) for dataset in [train_df, test_df]: # what d

下面的代码片段有一个for循环,在[]括号内有csv文件名

TRAIN_CSV = './train1.csv' # this comtains 100 entries
TEST_CSV = './test1.csv' # this contains 50 entries
train_df = pd.read_csv(TRAIN_CSV)
test_df = pd.read_csv(TEST_CSV)

for dataset in [train_df, test_df]:   # what does this mean here
     do something

当在[]括号中提供csv文件名时,for循环在这里做什么?

在本例中,括号表示列表。因此,您正在循环浏览一个仅由两个元素定义的列表
train_df
test_df

如何处理上面的[]包含.csv文件。那么它和链接指向的那个相同吗?这种语法被称为“序列解包”,谷歌可能更容易找到它for@Arpit我认为这个问题主要是由于对列表的内联表达式的混淆,而不是在列表中循环。这里train_df和test_df加载了一个.csv文件。那么循环在这里做什么呢?它将csv文件的内容分配给循环变量
dataset