r - Is there a selective replace function? Should it be done using a If statement or For loop?

Question

I am relatively new to R. I need some help with more of a find and replace function but it is a bit more selective.

The example datasets I am using can be derived through:

name_1 <- c("Madeline","Maximillian","Maxon","Mad","Marvin")
value <- c(2.3,3.4,7.5,1.9,16.2)
scoreboard_table <- data.frame(name_1,value)

name_2 <- c("Madeline","Maximillian","Maxon","Mad")
nickname_1 <- c("Mad","Max","M","N/A")
nickname_2 <- c("Madine","Maxim","N/A","N/A")
nickname_table <- data.frame(name_2,nickname_1,nickname_2)

I want to replace the name of the scoreboard table with the second nickname. In that case, it would result in scoreboard_table to turn into:

name_1 <- c("Madine","Maxim","Maxon","Mad","Marvin")
value <- c(2.3,3.4,7.5,1.9,16.2)
scoreboard_table <- data.frame(name_1,value)

I am sure if doing a for loop would be easier or making an if, else statement. How should I go about this overall?

Thank you for the help in advance. It is really appreciated.

标签： rreplacefind

Answer 1

You can perform a join and use coalesce to get names from nickname_2.

library(dplyr)

left_join(scoreboard_table, nickname_table, by = c('name_1' = 'name_2')) %>%
  transmute(name_1 = coalesce(nickname_2, name_1), 
            value) -> scoreboard_table

scoreboard_table

#  name_1 value
#1 Madine   2.3
#2  Maxim   3.4
#3  Maxon   7.5
#4    Mad   1.9
#5 Marvin  16.2

If they are not already change the "N/A" values to real NA in your data.

nickname_table[nickname_table == 'N/A'] <- NA