[R] Data length mismatch.

[Gabor Grothendieck]

Here is a second solution.  This one uses sqldf instead of zoo:

library(zoo)
sqldf("select A.x - ifnull(B.x, 0) from A left join B using(DayOfYear)")

See
http://sqldf.googlecode.com

On Sat, Jul 26, 2008 at 5:26 PM,  <rkevinburton at charter.net> wrote:
> 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 at 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.
>