How to reorder levels

Question

I have the following dataframe:

          Accession Order
1          CP000517  7
2          CP002081  8
3          CP002427  9
4          CP002429 10
5  CP002430_plasmid 11
6          CP003799 12
7          CP009907 13
8  CP009908_plasmid 14
9          CP011386 15
10         CP012381 16
11         CP016827 17
12              One 3
13      One_plasmid 4
14              Two 5
15      Two_plasmid 6
16            Three 1
17    Three_plasmid 2

Now I want to have the order according to the column "Order". Also the levels of "Accession" have to have this level-order...

Tried that already, but then the first column (rownumbers) doesn't change accordingly) — Michael, Feb 03 '17 at 08:29
http://stackoverflow.com/questions/1296646/how-to-sort-a-dataframe-by-columns — Sathish, Feb 03 '17 at 08:37

akrun · Accepted Answer · 2017-02-03T08:35:40.697

We just need to use order

df2 <- df1[order(df1$Order),]
row.names(df2) <- NULL
df2$Accession <- factor(df2$Accession, levels = unique(df2$Accession))

Or using tidyverse

library(dplyr)
df1 %>%
   arrange(Order) %>%
   mutate(Accession = factor(Accession, levels = unique(Accession)))

Or using data.table

library(data.table)
setDT(df1)[order(Order)][, Accession := actor(Accession, levels = unique(Accession))]

How to reorder levels

1 Answers1