How to randomly select polygons
Thank you very much Josiah, That works for me. Manuel El lun, 23 sept 2024 a las 15:54, Josiah Parry (<josiah.parry at gmail.com>) escribi?:
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 Sp?nola <mspinola10 at 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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