Want to mutate values of one category with duplicate values from another category in R-CodePudding

I have a Weather dataset with categorical values in a column named "City". In that, a city "Ahmedabad" is missing values entirely for the year 2019. Upon searching I found that "Hyderabad" double the number of values for the same year. I would like to extractpic of duplicate entries one set of values from "Hyderabad" and place that in "Ahmedabad"

CodePudding user response：

You could try this approach, using tidyverse and lubridate

library(tidyverse)
library(lubridate)

dt = dt %>% arrange(City, Date)
bind_rows(
  dt %>% filter(City!="Hyderabad" | year(Date)!=2019),
  dt %>% filter(City=="Hyderabad" & year(Date)==2019) %>% 
    mutate(City=if_else(row_number()%%2==0,"Ahmedabad", City))
)

Or, using data.table

library(data.table)

dt = setDT(dt)[order(City,Date)]
rbind(
  dt[City!="Hyderabad" | year(Date)!=2019],
  dt[City=="Hyderabad" & year(Date)==2019][seq(1,.N,2), City:="Ahmedabad"]
)