splitSamples: splitSamples
In RRemelgado/CAWaR: CAWa Project Tools

Description Usage Arguments Details Value See Also Examples

View source: R/splitSamples.R

Aggregates a spatial object into regions.

1	splitSamples(x, y, z, agg.radius = agg.radius)

`x`	A SpatialPoints or a SpatialPolygons object.
`y`	A RasterLayer.
`z`	A vector.
`agg.radius`	Numeric element.

For each class in z, the function converts the elements in x into a raster layer using y as a basis. Then, it aggregates all pixels that are within a given distance of each other - defined by agg.radius using ccLabel. The output is a list consisting of:

region.id - Class dependent region label for each element in x.
region.frequency - Pixel count for each unique value in region.id.

A list.

phenoCropVal phenoCropClass

{

require(raster)
require(fieldRS)

# read raster data
r <- brick(system.file("extdata", "ndvi.tif", package="fieldRS"))

# read field data
data(fieldData)
fieldData <- fieldData[3:4,]

# find polygon clusters
k <- splitSamples(fieldData, r, fieldData$crop, agg.radius=30)
fieldData$ID <- as.factor(k$region.id)

# plot regions with labels
spplot(fieldData["ID"])

# show pixel count per region
head(k$region.frequency)

}