I have two vectos (list) that represent a years of data.  Each "row" is 
represented by the day of year and the quantity that was sold for that day. I 
would like to form a new vector that is the difference between the two years of 
data. A sample of A (and similarly B) looks like:

> A[1:5,]
  DayOfYear    x
1         1 1429
2         2 3952
3         3 3049
4         4 2844
5         5 2219
> 

D <- A - B

This works just fine if A and B are both the same length. How is the best way 
to handle the situation where A and B are of different lengths? If the day of 
year exists in both vectors (lists) then I just want the coorespondng "row" in 
D to be the difference btween A and B values. If the "row" doesn't exist in 
either A or B then the difference should be treated as if the missing "row" was 
zero. Is this feasible?

Thank you.

Kevin

______________________________________________
R-help@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.

Reply via email to