[R] create and save a simulated dataset

[Rui Barradas]

Hello,

Once you formulate the problem properly, it's not hard to solve it in R.

Bert's questions should be answered before continuing. I'll make two 
assumptions, not present in your post.
All diameters are assumed independent and to follow the same uniform 
distribution. (iid scenario; the two assumptions you have to decide about.)

With these in mind, you can get some inspiration from the following 
code. It produces 10 vectors of a random numbers of trees of random 
diameters.


min.diam <- 1  # trees' diameters
max.diam <- 2  #
max.trees <- 10  # trees per stand
lapply(1:10, function(i) runif(sample(max.trees, 1), min.diam, max.diam))


Hope this helps,

Rui Barradas

Em 02-02-2013 20:10, Giovanna Ottaviani escreveu:
> Hello,
> I am trying to learn how to create a simulated dataset of a forest stand:
> I must simulate 10 stands, for each of the stands I have been creating a random number of trees. For each tree I should create a random diameter.
> The problem I have is that I cannot use a matrix because the length of the three items is different. I was trying with list but I have no clue on how to make a dataset out of them... tried "merge"....
> Anyone has some clever suggestion?
> THANK you !!
> Giovanna
>
>
> Giovanna Ottaviani Aalmo
> Stipendiat/Ph.D. Student
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