dd <- data.frame(b = factor(c("Hi","Med","Hi","Low"), levels = c("Low","Med","Hi"), ordered = TRUE), x = c("A","D","A","C"), y = c(8,3,9,9), z = c(1,1,1,2))sort by column z (descending) then by column b (ascending)1. dd[with(dd, order(-z, b)),]2. dd[ order(-dd[,4], dd[,1]),]
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