[R] Creating data frame from existing data frame

[Dimitris Rizopoulos]

well, first you could have a look at

?"[.data.frame"
?subset

and then check the following:

dat <- data.frame(year = sample(seq(2000, 2008, 2), 100, TRUE), y =
rnorm(100))

subset(dat, year == 2002)
dat[dat$year == 2002, ]

# or

subset(dat, year > 2002)
dat[dat$year > 2002, ]


I hope it helps.

Best,
Dimitris


>
> I'm new to R, using it for an engineering stats class, and the first
> project
> is focused on creating data frames and plotting graphs. So far I have
> imported a set of data from a text file and saved it as a variable (using
> the read.table() function). One of the columns of the data consists of
> years, and I'm supposed to create a data frame that only consists the the
> date from one given year (ie. I need to scan the Year column, pick out the
> specific year, and include those rows). I'm pretty sure I have to use
> data.frame() to do this, but I don't know what arguments would pick out
> rows
> from a particular year (and keep the headers of the columns intact in the
> new data frame). Beyond this, I need to plot it and export it to an image
> file, which I can do myself.
>
> Can someone please tell me the arguments to data.frame() that would
> achieve
> this (or better yet, point me to a good list of functions and arguments in
> addition to this).
>
> Thanks for your help,
>
> Josh
> --
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>
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-- 
Dimitris Rizopoulos
Assistant Professor
Department of Biostatistics
Erasmus University Medical Center

Address: PO Box 2040, 3000 CA Rotterdam, the Netherlands
Tel: +31/(0)10/7043478
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