[R] How to set a filter during reading tables

[guox at ucalgary.ca]

Thanks, Juliet.
It works for filtering columns.
I am also wondering if there is a way to filter rows.
Thanks again.
-james

> One can use colClasses to set which columns get read in. For the
> columns you don't
> want you can set those to NULL. For example,
>
> cc <- c("NULL",rep("numeric",9))
>
> myData <-
> read.table("myFile.txt",header=TRUE,colClasses=cc,nrow=numRows).
>
>
> On Wed, May 27, 2009 at 12:27 PM,  <guox at ucalgary.ca> wrote:
>> We are reading big tables, such as,
>>
>> Chemicals <-
>> read.table('ftp://ftp.bls.gov/pub/time.series/wp/wp.data.7.Chemicals',header
>> = TRUE, sep = '\t', as.is =T)
>>
>> I was wondering if it is possible to set a filter during loading so
>> that
>> we just load what we want not the whole table each time. Thanks,
>>
>> -james
>>
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>>
>
>
>