A single numeric value, or 0 when no non-zero, non-NA weight
remains.
Arguments
w
Numeric vector of edge weights. NA and zero entries are
dropped before aggregation.
method
Aggregation method: "sum", "mean", "median", "max", "min",
"prod", "density", "geomean". Default "sum". Any other value is an error.
n_possible
Number of possible edges (used only by
method = "density"; when NULL or not positive, the number of
surviving weights is used as the denominator instead).