If then statement in R - replacing based on value-CodePudding

I have a very large file where I have merged two customer databases. The key is the ID. Where the customer name did not match it shows an NA. I need to accomplish a simple if/then statement where if there is "NA" in column NAME_1 the DESIRED OUTCOME NAME is what is in NAME_2, else use what is in NAME_1

I attempted the following code but get errors

df <- df %>% if (df$NAME_1 == "NA") rename(df$NAME_1 == df$NAME_2)

CodePudding user response：

Simply done with

df$NAME_1[is.na(df$NAME_1)] <- df$NAME_2[is.na(df$NAME_1)]

This is just subsetting the values in each of the vectors to elements in positions where it is NA in NAME_1

CodePudding user response：

a solution with dummy data acording to the info you supplied:

df <- data.frame(ID = c(1,6,3,5,6,2,8,9),
                 NAME_1 = c(NA, "STEVE", NA, "JULIE", "BOB", "AMY", NA, "BRUCE"),
                 NAME_2 = c("MARY", "STEVE", "JAN", "JULIE", "BOB", "AMY", "FRANK", "BRUCE"))

library(dplyr)
df %>% 
    dplyr::mutate(NEW_COLUMN = ifelse(is.na(NAME_1), NAME_2, NAME_1))

CodePudding user response：

Using ifelse from base R,

df$'DESIRED OUTCOME NAME' = ifelse(is.na(df$NAME_1), df$NAME_2, df$NAME_1)

CodePudding user response：

In this particular case, the simplest solution would be to use dplyr::coalesce

library(dplyr)

df %>% mutate(`DESIRED OUTCOME NAME` = coalesce(NAME_1, NAME_2))

  ID NAME_1 NAME_2 DESIRED OUTCOME NAME
1  1   <NA>   MARY                 MARY
2  6  STEVE  STEVE                STEVE
3  3   <NA>    JAN                  JAN
4  5  JULIE  JULIE                JULIE
5  6    BOB    BOB                  BOB
6  2    AMY    AMY                  AMY
7  8   <NA>  FRANK                FRANK
8  9  BRUCE  BRUCE                BRUCE