Re: [R] creating a list of lists

From: Eric Archer <eric.archer_at_noaa.gov>
Date: Sun 07 Jan 2007 - 21:49:41 GMT

Howabout using 'lapply'?

forest <- lapply(1:10, function(level) {   # do some other things here
  # create and return a random forest
   randomForest(x = x.level, y = z.level, ntree = trees) })

# give meaningful names
names(forest) <- paste("level", 1:10, sep = "_")  

Paul Boutros wrote:
> Hello,
>
> I'm trying to create a series of randomForest objects, basically in a
> loop like this:
>
> forests <- list();
>
> for (level in 1:10) {
>
> # do some other things here
>
> # create a random forest
> forest <- randomForest(
> x = x.level,
> y = z.level,
> ntree = trees
> );
>
> forests <- c(forests, forest);
>
> }
>
>
> But instead of creating a list of 10 forests, this creates a list of
> 180 elements, 18 for each forest. Is there a way to create a list of
> randomForest objects for use later on in code like:
>
> for (forest in forests) {
> values <- predict(forest, data);
> # do things with these predicted values
> }
>
> Sincerely,
> Paul
>
> ______________________________________________
> R-help@stat.math.ethz.ch mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.
>

-- 

Eric Archer, Ph.D.
NOAA-SWFSC
8604 La Jolla Shores Dr.
La Jolla, CA 92037
858-546-7121,7003(FAX)
eric.archer@noaa.gov


"Lighthouses are more helpful than churches."
    - Benjamin Franklin

"...but I'll take a GPS over either one."
    - Craig George

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Received on Mon Jan 08 08:55:37 2007

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