r中的條件過去值

Question

我得到的數據幀具有可變的列數，應將行（粘貼）值連接在一起，形成最終的列（摘要），如下所示：

df <- data.frame(V1 = c("Adam", NA, "Tailor", "Daisy"),
                 V2 = c(NA, "Patrick", "Louis", NA), 
                 V3 = c(NA, "Ella", "Richard", "Laura"),
                 V4 = c("Norbert", NA, "Peter", NA),
                 stringsAsFactors = F)

final <- paste0(ifelse(is.na(df$V1), "" , paste0(df$V1,", ")), 
                ifelse(is.na(df$V2), "",  paste0(df$V2,", ")), 
                ifelse(is.na(df$V3), "",  paste0(df$V3,", ")), 
                ifelse(is.na(df$V4), "", df$V4))

> final
[1] "Adam, Norbert"                 "Patrick, Ella, "               "Tailor, Louis, Richard, Peter"
[4] "Daisy, Laura,

如何刪除姓氏后面的“，”？ 我可以在姓氏之前替換“和”嗎？ 另外，可以根據輸入數據框中的列數進行調整嗎？

提前致謝

Answer 1

嘗試使用以下代碼：

apply(df,1,function(i){gsub("\\,"," and", toString(i[!is.na(i)]))})