目录
[2.1 通过索引[]](#2.1 通过索引[])
[2.2符号访问](#2.2符号访问)
[2.3 attach访问](#2.3 attach访问)
[2.4 with访问](#2.4 with访问)
1数据框的合并
当每个内容存储为单独的向量,data.frame可以进行这些内容单独数据框合并。
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2数据框的访问
2.1 通过索引[]
[i]输出对应的列
[i,]输出对应的行
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2.2符号$访问
state$state.abb
取出$后指定的这一列state.abb。
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那么在plot绘制时就可以用到:
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2.3 attach访问
加载数据框到R搜索目录中
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利用attach将mtcars加载数据框到R搜索目录中,之后就可以直接输入列名就可以了
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detach(mtcars)取消加载
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2.4 with访问
with(mtcars,{mpg})
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