[R] Interpolation of data

Hello, I have the data whcih are not balanced (several missing observations), and one possibility is t use interpolation method to get the information missing in this series from other series. Does anybody know how I can program interpolation of series1 (which ahs missing observations) and series

[R] specifying data

Hello, I have to merge several serie by "date". I used: cb<-merge(cbds,cbbond,by=c("date"),all=T). I have the daily and the high frequency data. Unfortunately, the programm did not sort by "sort" my data in a chronological manner. Is there any possibility to do this in R?. Thanks in advance, Silk