How can I find and replace decimal numbers among whole numbers in a column in R?

Question

I am working with a dataset that came from a machine. In one column, all values are whole numbers without any decimals, but sometimes the machine recorded some numbers with

Answer 1

If your dataframe is called df and the column is V1 you can identify values which are decimals by

df$V1 %% 1 != 0
#[1] FALSE FALSE FALSE FALSE FALSE FALSE FALSE  TRUE FALSE FALSE FALSE FALSE FALSE
#[14] FALSE FALSE FALSE  TRUE FALSE FALSE FALSE FALSE FALSE

If you want to replace these values (let's say with NA)

df$V1[df$V1 %% 1 != 0] <- NA

If you want to drop decimal values you can do :

df <- df[df$V1 %% 1 == 0, , drop = FALSE]

Answer 2

simply use the ifelse() function

 d<-c(1, 1, 1, 2, 3, 4, 5, 8.6, 6, 7, 7, 7, 7, 8, 9, 9, 4.2, 1, 1, 1, 2, 3)


e<-ifelse(d==as.integer(d), d, NA) # instead of NA you can insert any value you want. 

result:

1  1  1  2  3  4  5 NA  6  7  7  7  7  8  9  9 NA  1  1  1  2  3

you said you didn't want to just round the values but if it was an option a simple d<-as.integer(d) would solve the problem as well.