数据框排序 data.frame order

# sorting examples using the mtcars dataset
attach(mtcars)

# sort by mpg
newdata <- mtcars[order(mpg),]

# sort by mpg and cyl
newdata <- mtcars[order(mpg, cyl),]

#sort by mpg (ascending) and cyl (descending)
newdata <- mtcars[order(mpg, -cyl),]

detach(mtcars)

 

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newdata <- mtcars[order(mtcars$mpg),]

 

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dd[with(dd, order(-z, b)), ]
  ## sort by column Z and B

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