我正在浏览dplyr上的DataCamp类。他们让我加载'航班'数据,然后要求我创建一个名为'承运人'的新列,用他们的实际名称替换每个航空公司代码。该解决方案如下所示:将列添加到数据框并重新编码
hflights <- tbl_df(hflights)
names <- c("AA" = "American", "AS" = "Alaska", "B6" = "JetBlue", "CO" = "Continental",
"DL" = "Delta", "OO" = "SkyWest", "UA" = "United", "US" = "US_Airways",
"WN" = "Southwest", "EV" = "Atlantic_Southeast", "F9" = "Frontier",
"FL" = "AirTran", "MQ" = "American_Eagle", "XE" = "ExpressJet", "YV" = "Mesa")
hflights["Carrier"] <- names[hflights$UniqueCarrier]
我想通了,如何做到这一点,而这个工作,但它并不真正清楚,我到底是什么R为这里做什么。我知道我正在给hflights数据框添加一个新列,但我不清楚R是如何(或为什么)用运营商代码替换运营商名称。