[R] looking up value from a pair of vectors

[Stefann Jonsso]

Hello  R community.

Can anyone inform me how to solve this short problem? I have a dataset that 
I want to recode according to a  pair of short numerical vectors. Here is a 
short example:


# Start R code

map1 <- matrix(ncol=3, byrow=T,c( 197796,"label0",1,
197797,"label1",2,
197798,"label2",3,
197799,"label3",4,
197800,"label4",5))

xx <- as.integer(map1[,1])
lab <- map1[,2]
yy <- as.integer(map1[,3]


data1a <- c(197797, 197798, 197799, 197800,
           197797, 197797, 197797, 197797)



data1b <- some.function.or.combinaion.of.few(data1a,xx,yy)

# desired result for data1b

data1b
2 3 4 5 2 2 2 2

# End R code


data1a is always longer than xx.
all numerical entries in data1a are members of xx. (in the more general 
problem, the the number 197796 may or may not be included in data1a)
value in data1a that are not members of xx would produce a "Na"



Thanks in advance for all replies,
Stefan Jonsson