relative.position {RSAGA} | R Documentation |
Relative Topographic Position
Description
relative.position
and relative.rank
are used with focal.function()
to determine the relative value of a grid cell compared to its surroundings, either on a metric scale or based on ranks.
Usage
relative.position(x)
relative.rank(x, ties.method = "average")
Arguments
x |
a square matrix with the grid data from the moving window, possibly containing |
ties.method |
see |
Value
If x
is provided, a numeric value in the interval [0,1] is returned.
If x
is missing, a character vector of same length giving suggested variable (or file) names, here "relpos"
and "relrank"
, respectively. See focal.function()
for details.
See Also
focal.function()
, rank()
, centervalue()
Examples
m = matrix( round(runif(9,1,10)), ncol=3 )
print(m)
relative.position(m)
relative.rank(m)
## Not run:
focal.function("dem",fun=relative.rank,radius=5)
focal.function("dem",fun=relative.position,radius=5)
relrank = as.vector(read.ascii.grid("relrank")$data)
relpos = as.vector(read.ascii.grid("relpos")$data)
plot(relpos,relrank,pch=".")
cor(relpos,relrank,use="complete.obs",method="pearson")
## End(Not run)
[Package RSAGA version 1.4.0 Index]