Я хочу преобразовать NA в определенный символ, основываясь на заданном значении переменной для этих конкретных имен.Пример запроса
df1 = data.frame(session=c("breakfast","breakfast", "breakfast", "NA","lunch","lunch","lunch","NA","dinner","dinner","dinner","NA"))
Где NA мне нужен такой результат
df2 = data.frame(session=c("breakfast","breakfast", "breakfast", "breakfast Total","lunch","lunch","lunch","lunch Total","dinner","dinner","dinner","dinner Total"))