Conditional replace a list element in rstudio

[vally]

Hello I have a dataframe like the below:

 path.vec                           source.vec                        
1 apple	                            Tuesday	                       
2 lemon	                            Monday	                       
3 orange	                        Wednesday	                       
4c("apple", "lemon", "grape")	    c("Friday", "Monday", "Sunday")     
5c("cheery", "lemon", "grape")	    c("Saturday", "Monday", "Sunday")      
6c("apple", "lemon", "apple")	    c("Thursday", "Monday", "Sunday")   

just 2 variables: path.vec and source.vec. Both are collecting 2 different shadows of the same data

[![enter image description here][1]][1]

I would like simply to swap elements between lists with same index when a condition is met.

Ratio should be:

if df$path.vec contains "apple" swap with df$source.vec same index element

I have tried the below:

df$path.vec <- ifelse(grepl("apple", df$path.vec), df$source.vec, df$path.vec)

but this is changing all the elements, when there is at least one element =="apple", while I want to change just the element "apple". I'm thinking that probably i need to find indexes first and after to base my swap on the index?
I have tried

ind  <- which(df$path.vec %in% c("apple"))

but in my real data set this is an error

Error in `$<-.data.frame`(`*tmp*`, path.index, value = 1:6) : 
 replacement has 6 rows, data has 33422

because it's indexing just when apple is the only element of the list.

I have also tried

df$path.index <- match("apple", df$path.vec)

but this results just in 1 every single row of my dataframe.

Is this one the best way to approach this?

Eventually I would like to obtain another column like the below:

path.final                                               
1 Tuesday	                             	                       
2 lemon	                                                     
3 orange	                                            
4c("Friday", "lemon", "grape")	      
5c("cheery", "lemon", "grape")	   
6c("Thursday", "lemon", "Sunday")

Cheers,

[osenan]

@vally

c("Thursday", "Monday", "Sunday")

My answer would be that you transform your two columns into lists using as.list or similar and then perform grep within a lapply. Here is the code:

path.vec = list("1" = "apple",
                "2" = "lemmon",
                "3" = "orange",
                "4" =c("apple", "lemon", "grape"),
                "5"=c("cheery", "lemon", "grape"),
                "6"=c("apple", "lemon", "apple"))

source.vec = list("1" = "Tuesday",
                  "2" = "Monday",
                  "3" = "Wednesday",
                  "4" = c("Friday", "Monday", "Sunday"),
                  "5" = c("Saturday", "Monday", "Sunday"),
                  "6" = c("Thursday", "Monday", "Sunday"))

path.final <- lapply(1:length(path.vec), function(x) {
    res <- path.vec[[x]]
    pos <- grep("apple", res, fixed = T)
    if(length(pos) > 0) res[pos]  <- source.vec[[x]][pos]
    res
})

path.final

[vally]

Hello Osenam!

thank you very much it worked brilliant.
just for reference, my vectors were already lists but didn't have names, I have added names easily:

names(path.vec) <- c(1:6)

Cheers