[R] Sum Question

[Edgar Alminar]

>> I did this:
>> 
>> library(data.table)
>> 
>> dd <- data.table(bl)
>> dd[,sum(as.integer(CONTTIME)), by = SCRNO]
>> 
>> (I used as.integer because I got an error message: sum not meaningful for factors)
>> 
>> And got this:
>> 
>>            SCRNO  V1
>>  [1,] HBA0020036 111
>>  [2,] HBA0020087  71
>>  [3,] HBA0020209 140
>>  [4,] HBA0020213 189
>>  [5,] HBA0020222 174
>>  [6,] HBA0020292 747
>>  [7,] HBA0020310  57
>>  [8,] HBA0020317 291
>>  [9,] HBA0020365 417
>> [10,] HBA0020366 124
>> 
>> All the sums are way too big. Is there something making it not add up correctly?
>> 
>> Original dataset:
>> 
     RID      SCRNO VISCODE RECNO CONTTIME
338   43 HBA0020036      bl     1        9
1187  95 HBA0020087      bl     1        3
3251 230 HBA0020209      bl     2        3
3258 230 HBA0020209      bl     1       28
3321 235 HBA0020213      bl     2        5
3351 235 HBA0020213      bl     1        6
3436 247 HBA0020222      bl     1        5
3456 247 HBA0020222      bl     2        4
4569 321 HBA0020292      bl    13        2
4572 321 HBA0020292      bl     5       13
4573 321 HBA0020292      bl     1       25
4576 321 HBA0020292      bl     7        5
4578 321 HBA0020292      bl     8        2
4581 321 HBA0020292      bl     4        4
4582 321 HBA0020292      bl     9        5
4586 321 HBA0020292      bl    12        2
4587 321 HBA0020292      bl     6        2
4590 321 HBA0020292      bl    10        3
4591 321 HBA0020292      bl    11        7