firstflowsg: Flow Selection Based on Global Criteria

In flows: Flow Selection and Analysis

Description

Flow selection based on global criteria.

Usage

firstflowsg(mat, method = "nfirst", k, ties.method = "first")

Arguments

mat	A square matrix of flows.
method	A method of flow selection, one of "nfirst", "xfirst" or "xsumfirst": nfirst selects the k first flows of the matrix, xfirst selects flows greater than k, xsumfirst selects as many flows as necessary so that their sum is at least equal to k.
k	Selection threshold.
ties.method	In case of equality with "nfirst" method, use "random" or "first" (see rank).

Details

As the output is a boolean matrix, use element-wise multiplication to get flows intensity.

Value

A boolean matrix of selected flows.

See Also

firstflows, domflows

Examples

# Import data
data(nav)
myflows <- prepflows(mat = nav, i = "i", j = "j", fij = "fij")

# Remove the matrix diagonal
diag(myflows) <- 0

# Select the 50 first flows of the matrix
flowSel <- firstflowsg(mat = myflows, method = "nfirst", ties.method = "first",
                       k = 50)
statmat(mat = myflows * flowSel, output = "none")

# Select all flows greater than 2000
flowSel <- firstflowsg(myflows, method = "xfirst", k= 2000)
statmat(mat = myflows * flowSel, output = "none")

# Select flows that represent at least 50% of the matrix flows
k50 <- sum(myflows)/2
flowSel <- firstflowsg(mat = myflows, method = "xsumfirst", k = 150000)
statmat(mat = myflows * flowSel, output = "none")

flows documentation built on May 2, 2019, 7:25 a.m.