[R-sig-Geo] Circular/square sample function for extract coordinates and marks in *ppp object

[ASANTOS]

Dear r-sig-geo members,

I've to know if there is a function for sample for extract coordinates 
and marks of a marked planar point pattern object? In my example:

library(spatstat)

## Using a longleaf data set
longleaf
#Marked planar point pattern: 584 points
#marks are numeric, of storage type� �double�
#window: rectangle = [0, 200] x [0, 200] metres

There is the spsample(x, n, "random") for example, but this function 
sample random points inside longleaf$window area and doesn't work for marks.

I've like a function that extract longleaf points coordinates and marks 
inside a circular area (eg. 1 metres) or square area (eg. 1 metes h x w) 
around n random sample points and a data frame or better a new marked 
planar point patter object as output.

Is there this type of function implemented in R?

Thanks in advanced,

Alexandre

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Alexandre dos Santos
Geotechnologies and Spatial Statistics applied to Forest Entomology
Instituto Federal de Mato Grosso (IFMT) - Campus Caceres
Caixa Postal 244 (PO Box)
Avenida dos Ramires, s/n - Distrito Industrial
Caceres - MT - CEP 78.200-000 (ZIP code)
Phone: (+55) 65 99686-6970 / (+55) 65 3221-2674
Lattes CV: http://lattes.cnpq.br/1360403201088680
OrcID: orcid.org/0000-0001-8232-6722
ResearchGate: www.researchgate.net/profile/Alexandre_Santos10
Publons: https://publons.com/researcher/3085587/alexandre-dos-santos/
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