subset dataframe by rows using character vector?

Yes! that's it. Any chance you can tell me how to select everything  
but those plotNames? Basically a reverse subset? I don't know these  
character matching functions very well.

I very much appreciate your help, thanks again.

Zack

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CC: r-help at r-project.org
From: ba208 at exeter.ac.uk
To: zack_holden at hotmail.com
Subject: Re: [R] subset dataframe by rows using character vector?
Date: Tue, 14 Apr 2009 15:56:45 +0100

Is this what you want?

plotNames <- c("plot1", "plot2", "plot3") # plot is probably best
left as the name of the base function
full.data[full.data$PLOTID %in% plotNames, ] # note the comma


HTH,

baptiste

On 14 Apr 2009, at 15:20, zack holden wrote:

Dear List,

I'm stuck on what seems like a simple indexing problem, I'd be very
grateful to anyone willing to help me out.

I queried a dataframe which returns a character vector called
"plot". I have another dataframe from which I want to subset or
select only those rows that match "plot". I've tried subset, and
also the "which" command.


plot <- c("plot1", "plot2", "plot3") # character
vector used to select rows from data

# create fake data from to try out subset
v1 <- c(2,5,6,4,3)
PLOTID <- c("plot1", "plot2", "plot3", "plot4", "plot5")
full.data <- cbind(v1, PLOTID)
full.data <- as.data.frame(full.data)

# first attempt
test <- which(full.data$PLOTID == plot)

# second attempt
test <- full.data[full.data$PLOTID == plot]


I'm sure there is a simple solution here, but I'm unable to figure
it out.

Thanks for any suggestions,

Zack