R help - Jan 2014 - Is this a bug or am I making a mistake?

I have a data frame that I am extracting some records from and noticed 
the following issue

I originally used tmp <- subset(dd, dd$EVYEAR==2012 &
dd$EVMONTH=='02')

and noticed that I wasn't ending up with all of the records I should 
have; however, when I used

tmp <- dd[dd$EVYEAR==2012 & dd$EVMONTH=='02',]

I did get all of the records I should have.

I thought the two forms were equivalent, am I mistaken?

Hi Walter,

I can't reproduce your results. Please provide some data that
demonstrates the problem.

http://stackoverflow.com/questions/5963269/how-to-make-a-great-r-reproducible-example

subset() and [ differ in their handling of NA values, and you don't
need the dd$ in the arguments to subset().

But those don't explain your result given the information provided.
Please provide more information.

Sarah


On Mon, Jan 6, 2014 at 12:06 PM, Walter Anderson <wandrson01 at gmail.com>
wrote:
> I have a data frame that I am extracting some records from and noticed the
> following issue
>
> I originally used tmp <- subset(dd, dd$EVYEAR==2012 &
dd$EVMONTH=='02')
>
> and noticed that I wasn't ending up with all of the records I should
have;
> however, when I used
>
> tmp <- dd[dd$EVYEAR==2012 & dd$EVMONTH=='02',]
>
> I did get all of the records I should have.
>
> I thought the two forms were equivalent, am I mistaken?
>
-- 
Sarah Goslee
http://www.functionaldiversity.org