test_that("laplacian matrix correct", {
  g <- igraph::graph.full(5)
  igraph::E(g)$sign <- -1
  L <- laplacian_matrix_signed(g)
  expect_equal(diag(L), rep(4,5))
})

test_that("laplacian matrix norm correct", {
  g <- igraph::graph.full(5)
  igraph::E(g)$sign <- -1
  L <- laplacian_matrix_signed(g,norm = TRUE)
  L_true <- structure(c(1, 0.25, 0.25, 0.25, 0.25, 0.25, 1, 0.25, 0.25, 0.25,
              0.25, 0.25, 1, 0.25, 0.25, 0.25, 0.25, 0.25, 1, 0.25, 0.25, 0.25,
              0.25, 0.25, 1), .Dim = c(5L, 5L))
  expect_equal(L,L_true)
})

test_that("laplacian matrix error graph correct", {
  expect_error(laplacian_matrix_signed(g=5))
})

test_that("laplacian matrix error sign correct", {
  g <- igraph::graph.full(5)
  expect_error(laplacian_matrix_signed(g))
})

#
# test_that("laplacian angle sign is correct", {
#   g <- igraph::graph.full(3)
#   igraph::E(g)$sign <- 1
#   ang <- laplacian_angle(g)
#   ang_true <- c(0.95531662, -0.61547971, -0.61547971)
# })
#
# test_that("laplacian angle sign is correct", {
#   g <- igraph::graph.full(3)
#   igraph::E(g)$type <- "P"
#   ang <- laplacian_angle(g,"complex",attr="type")
#   ang_true <- c(0, 0, 3.14159265)
# })