将特定列中的 NA 值转换为 R 中的“”字段

Question

I have a dataset, df that I reading in from Excel to R. For some reason, when reading in the file, R sets all the empty fields to NA. How do I reverse this? I want the NA values in the column to be converted back to empty cells.

                      Subject     Value
                      hello       NA
                      hello       NA
                      hello       NA

I would like:

                      Subject     Value
                      hello       
                      hello       
                      hello       

Here is the dput:

  structure(list(Subject = structure(c(1L, 1L, 1L), .Label = "hello", class = "factor"), 
  Value = c(NA, NA, NA)), class = "data.frame", row.names = c(NA, 
 -3L))

This is what I have tried:

  df[is.na(df$Value)]   <- " " 

.

I do not know if this structure is correct Any help is appreciated.

Answer 1

We need to assign the same column name

df$Value[is.na(df$Value)] <- ""

Instead, if we do the subset on the whole dataset, it would result in error

df1[is.na(df1$Value)]

Error in [.data.frame (df1, is.na(df1$Value)) : undefined columns selected

---

With tidyverse , we can also use replace_na

library(dplyr)
library(tidyr)
df1 <- df1 %>%
          mutate(Value = replace_na(Value, ""))
df1
#    Subject Value
#1   hello      
#2   hello      
#3   hello