[R] question on aggregate
Altaweel, Mark R.
maltaweel at anl.gov
Fri May 1 23:07:30 CEST 2009
I am trying to sum column information in a list with 3 instances.
ID Traversed ID Traversed ID Traversed
1 5 1 7 1 8
2 8 2 11 2 7
3 11 3 22 3 16
What I want to do is sum the Traversed variable across all these instances so I can get a total value for Traversed for each ID column. So the end output should look like the following:
Basically, just sum up the columns by id.
I am using the aggregate function, but it is not working.
This is what I do:
agW<-aggregate(rres,rres[c('ID')],sum) //rres is the list
Error in FUN(X[[1L]], ...) : argument "INDEX" is missing, with no default //the error message I get
As you can see, I get the index error when I try this above.
Can anyone help?
Thanks in advance.
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