r - Bin data into quantiles using cut - getting missing values -

i have dataframe:

a <- matrix(c(1,2,3,4), 2,2) colnames(a) <- c("a", "b") df <- as.data.frame(a)  > df   b 1 1 3 2 2 4 

first, calculate quartilies of "a" column:

> quantile (df$a)   0%  25%  50%  75% 100%  1.00 1.25 1.50 1.75 2.00  

then, categorize column "b" using quartiles column "a":

> cat.b<-cut(df$b, quantile (df$a,)) > cat.b   [1] <na> <na>   levels: (1,1.25] (1.25,1.5] (1.5,1.75] (1.75,2] 

as can see, r gives na both "b" values above highest quartile of "a".

however, resulting "cat.b" vector like:

> cat.b [1] ">2"    ">2"   

could please tell me how in r.

thank you

the 2 values not in range. can circumvent making break. chose inf, can use finite value.

cat.b <- cut(df$b, c(-inf, quantile(df$a), inf)) #next line can done better, illustrates purpose levels(cat.b)[length(levels(cat.b))] <- ">2"  levels(cat.b)[1] <- "<1"  cat.b [1] >2 >2 levels: (1,1.25] (1.25,1.5] (1.5,1.75] (1.75,2] >2