threshold function

To go to higher level in the hierarchy.

This function transforms the current numeric vector or intensity data set into a "simplified black and white image" of this same data set: every value of disease intensity below and above a given threshold is given the value 0 and 1, respectively.

threshold(data, value, ...)

Arguments

• data: A numeric vector or an intensity object.
• value: All the intensity values lower or equal to this value are set to 0. The other values are set to 1.
• ...: Additional arguments to be passed to other methods.

Returns

A numeric vector or an intensity object.

Details

By default, everything above 0 is given 1, and 0 stays at 0. threshold

is thus useful to report a whole sampling unit as "healthy" (0), if no diseased individual at all was found within the sampling unit, or "diseased" (1) if at least one diseased individual was found.

Examples

my_incidence <- incidence(tomato_tswv$field_1929)
plot(my_incidence, type = "all")
my_incidence_clumped_1 <- clump(my_incidence, unit_size = c(x = 3, y = 3))
plot(my_incidence_clumped_1, type = "all")
my_incidence_thr <- threshold(my_incidence_clumped_1, value = 4)
plot(my_incidence_thr, type = "all")