比如df包含['a','b','c']列,想去掉'a'列
subset(df, select = -a )
https://stackoverflow.com/questions/6286313/remove-an-entire-column-from-a-data-frame-in-r
比如df包含['a','b','c']列,想去掉'a'列
subset(df, select = -a )
https://stackoverflow.com/questions/6286313/remove-an-entire-column-from-a-data-frame-in-r