[R-sig-Geo] How to randomly select polygons

[Josiah Parry]

I would take the same approach I would for most other things.

1. Count the number of observations
2. Define your sample size
3. Sample `n` from 1:N
4. Use those as an index to subset from

nc  <- sf::st_read(system.file("shape/nc.shp", package = "sf"))

n <- 10
idx <- sample(1:nrow(nc), n)
nc[idx, ]

On Mon, Sep 23, 2024 at 2:45 PM Manuel Spínola <mspinola10 using gmail.com> wrote:

> Dear list members,
>
> How can I select polygons at random from an sf or terra vector (polygon or
> multipolygon geometry).
>
> For example for the nc file:
>
> nc = st_read(system.file("shape/nc.shp", package="sf"))
>
> Manuel
>
>
> --
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