On Tue, Aug 5, 2008 at 11:59 AM, <[EMAIL PROTECTED]> wrote:
> I have a set of data that is basically sales figures for a given year. It has
> columns for Yeaqr, Day Of Year, Sku, SubCatetory, and Category. The first few
> lines of data look like:
> Year DayOfYear Sku Quantity CatId Category SubCategory
> 1 2007 1 100091 1 10862 HOLIDAY Christmas
> 2 2007 1 100138 1 11160 PET COSTUMES Famous (Licensed)
> 3 2007 1 100194 1 10749 HATS, WIGS & MASKS Wigs - Women's
> 4 2007 1 100432 1 10865 HOLIDAY Easter
> 5 2007 1 100911 1 10120 MEN Superheroes Men
>
> So I have the following to help me summarize the data by the various columns:
>
> library("reshape")
> t <- melt(t2007, id.var=c("DayOfYear","Category","SubCategory","Sku"),
> measure.var=c("Quantity"))
>
> The following seems to give me the sales for each day of the year:
>
> head(cast(t, DayOfYear ~ variable, sum))
> DayOfYear Quantity
> 1 1 861
> 2 2 1732
> 3 3 2124
> 4 4 1801
> 5 5 2147
> 6 6 1312
>
> Now I want to get the sales by day of year AND category. But the following
> doesnt seem right:
>
> head(cast(t, DayOfYear ~ Category ~ variable, sum))
> [1] NA 2 NA NA 2 NA
Have a look at
cast(t, DayOfYear ~ Category ~ variable, sum)
it's a 3d array - probably not what you want. You probably want
cast(t, DayOfYear + Category ~ variable, sum)
I'd suggest reading through the introduction to reshape pdf too.
Hadley
--
http://had.co.nz/
______________________________________________
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.
