Changing labels

Changing labels of levels

library(hflights)

## Warning: package 'hflights' was built under R version 3.3.2

# Way 1: convert variable (chr) to factor

hflights$UniqueCarrier<-as.factor(hflights$UniqueCarrier)

levels(hflights$UniqueCarrier)<-c("American","Alaska","JetBlue",'Continental',"Delta",   "Atlantic_Southeast","Frontier","AirTran","American_Eagle",                         "SkyWest","United","US_Airways","Southwest","ExpressJet","Mesa")

head(hflights)

##      Year Month DayofMonth DayOfWeek DepTime ArrTime UniqueCarrier
## 5424 2011     1          1         6    1400    1500      American
## 5425 2011     1          2         7    1401    1501      American
## 5426 2011     1          3         1    1352    1502      American
## 5427 2011     1          4         2    1403    1513      American
## 5428 2011     1          5         3    1405    1507      American
## 5429 2011     1          6         4    1359    1503      American
##      FlightNum TailNum ActualElapsedTime AirTime ArrDelay DepDelay Origin
## 5424       428  N576AA                60      40      -10        0    IAH
## 5425       428  N557AA                60      45       -9        1    IAH
## 5426       428  N541AA                70      48       -8       -8    IAH
## 5427       428  N403AA                70      39        3        3    IAH
## 5428       428  N492AA                62      44       -3        5    IAH
## 5429       428  N262AA                64      45       -7       -1    IAH
##      Dest Distance TaxiIn TaxiOut Cancelled CancellationCode Diverted
## 5424  DFW      224      7      13         0                         0
## 5425  DFW      224      6       9         0                         0
## 5426  DFW      224      5      17         0                         0
## 5427  DFW      224      9      22         0                         0
## 5428  DFW      224      9       9         0                         0
## 5429  DFW      224      6      13         0                         0

# Define labels 
lut<-c("AA"="American","AS"= "Alaska","B6"= "JetBlue","CO"= 'Continental',"DL"= "Delta", "EV"="Atlantic_Southeast","F9"= "Frontier","FL"= "AirTran","MQ"= "American_Eagle",                         "SkyWest","AU"= "United","US"= "US_Airways","WN"= "Southwest","XE"= "ExpressJet","YV"= "Mesa")

# Create a new variable named New_Carriername
library(hflights)

hflights$New_carriername<-lut[hflights$UniqueCarrier]