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 <mspinol...@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
>
>
> --
> *Manuel Spínola, Ph.D.*
> Instituto Internacional en Conservación y Manejo de Vida Silvestre
> Universidad Nacional
> Apartado 1350-3000
> Heredia
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> mspinol...@gmail.com
> Teléfono: (506) 8706 - 4662
> Sitio web institucional: ICOMVIS
> <http://www.icomvis.una.ac.cr/index.php/manuel>
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>
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