mNumber: Number of objects

Description Usage Arguments Value See Also Examples

View source: R/measure.operators.R

Description

Count the number of objects in a raster

Usage

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mNumber(obj, scale = "patch", layer = NULL)

Arguments

obj

[Raster*(1)]
The object to measure.

scale

[character(1)]
scale at which the area of objects should be calculated; possible values are "patch" and "class".

layer

[character(1)]
in case obj has several layers, specify here the layer for which the area of objects shall be calculated (by default, the first layer).

Value

For scale = "class" the number of unique values (classes) in the raster. For scale = "patch" the number of objects per distinc value (i.e. the number of patches per class).

See Also

Other generic metrics: mAdjacency, mArea, mPerimeter, mValues

Examples

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cat <- rtData$categorical
bin <- rBinarise(rtData$continuous, thresh = 40)

# the number ...
# ... per landcover type
mNumber(obj = cat, scale = "class")

# ... of patches per landcover type
mNumber(obj = cat, scale = "patch")

# ...  of certain values; from a binary raster, patches are 
# automatically determined
require(magrittr)
rBinarise(obj = cat, match = c(41, 44, 47)) %>%
  mNumber(scale = "patch", layer = "values_binarised")

mNumber(obj = bin, scale = "class")

EhrmannS/rasterTools documentation built on Feb. 4, 2019, 11:22 a.m.