tests/testthat/test-neighborhood.R

In igraph: Network Analysis and Visualization

test_that("ego works", {
  neig <- function(graph, order, vertices) {
    sp <- distances(graph)
    v <- unique(unlist(lapply(vertices, function(x) {
      w <- which(sp[x, ] <= order)
    })))
    induced_subgraph(graph, c(v, vertices))
  }

  g <- sample_gnp(50, 5 / 50)

  v <- sample(vcount(g), 1)
  g1 <- make_ego_graph(g, 2, v)[[1]]
  g2 <- neig(g, 2, v)
  expect_true(graph.isomorphic(g1, g2))

  #########

  nei <- function(graph, order, vertices) {
    sp <- distances(graph)
    v <- unique(unlist(lapply(vertices, function(x) {
      w <- which(sp[x, ] <= order)
    })))
    v
  }

  v1 <- ego(g, 2, v)[[1]]
  v2 <- nei(g, 2, v)
  expect_that(as.vector(sort(v1)), equals(sort(v2)))

  #########

  s <- ego_size(g, 2, v)[[1]]
  expect_that(s, equals(length(v1)))
})

test_that("mindist works", {
  g <- make_ring(10)
  expect_that(ego_size(g, order = 2, mindist = 0), equals(rep(5, 10)))
  expect_that(ego_size(g, order = 2, mindist = 1), equals(rep(4, 10)))
  expect_that(ego_size(g, order = 2, mindist = 2), equals(rep(2, 10)))

  unvs <- function(x) lapply(x, as.vector)

  n0 <- unvs(ego(g, order = 2, 5:6, mindist = 0))
  n1 <- unvs(ego(g, order = 2, 5:6, mindist = 1))
  n2 <- unvs(ego(g, order = 2, 5:6, mindist = 2))

  expect_that(lapply(n0, sort), equals(list(3:7, 4:8)))
  expect_that(lapply(n1, sort), equals(list(c(3, 4, 6, 7), c(4, 5, 7, 8))))
  expect_that(lapply(n2, sort), equals(list(c(3, 7), c(4, 8))))

  ng0 <- make_ego_graph(g, order = 2, 5:6, mindist = 0)
  ng1 <- make_ego_graph(g, order = 2, 5:6, mindist = 1)
  ng2 <- make_ego_graph(g, order = 2, 5:6, mindist = 2)

  expect_that(sapply(ng0, vcount), equals(c(5, 5)))
  expect_that(sapply(ng1, vcount), equals(c(4, 4)))
  expect_that(sapply(ng2, vcount), equals(c(2, 2)))

  expect_that(sapply(ng0, ecount), equals(c(4, 4)))
  expect_that(sapply(ng1, ecount), equals(c(2, 2)))
  expect_that(sapply(ng2, ecount), equals(c(0, 0)))
})