R help - Aug 2011 - Correct Syntax for subset.data.frame()

I want to create individual data.frames for each of the 8 param factors in
chemdata. The syntax I tried (based on Teetor's book, page 132) and R's
response are:
> ars <- subset(chemdata, select=c(site,sampdate,param,quant),
subset=(param
= "As"))
Error in subset.data.frame(chemdata, select = c(site, sampdate, param,  :
   'subset' must evaluate to logical

   I'm asking for columns of type factor, date, factor, and numeric. What
have I done incorrectly here?

Rich

I think you want

param == "As"

On Wednesday, August 31, 2011, Rich Shepard <rshepard@appl-ecosys.com>
wrote:
>  I want to create individual data.frames for each of the 8 param factors
in
> chemdata. The syntax I tried (based on Teetor's book, page 132) and
R's
> response are:
>
>> ars <- subset(chemdata, select=c(site,sampdate,param,quant),
subset=(param
>
> = "As"))
> Error in subset.data.frame(chemdata, select = c(site, sampdate, param,  :
>  'subset' must evaluate to logical
>
>  I'm asking for columns of type factor, date, factor, and numeric. What
> have I done incorrectly here?
>
> Rich
>
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>
-- 
Jim Holtman
Data Munger Guru

What is the problem that you are trying to solve?

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