tests/testthat/test_dynamic_knapsack.R

In drowsygoat/lab6.knapsack: Solves Knapsack problem in three ways: brute force, dynamic programming and greedy approximation.

context("dynamic_knapsack")

suppressWarnings(RNGversion(min(as.character(getRversion()),"3.5.3")))
set.seed(42, kind = "Mersenne-Twister", normal.kind = "Inversion")
n <- 2000
knapsack_objects <- data.frame(
        w=sample(1:4000, size = n, replace = TRUE),
        v=runif(n = n, 0, 10000)
)

test_that("Correct object is returned", {
        expect_silent(dk <- dynamic_knapsack(x = knapsack_objects[1:8,], W = 3500))
        expect_named(dk, c("value", "elements"))
})


test_that("functions rejects errounous input.", {
        expect_error(dynamic_knapsack("hej", 3500))
        expect_error(dynamic_knapsack(x = knapsack_objects[1:8,], W = -3500))
})

test_that("Function return correct results.", {
        dk <- dynamic_knapsack(x = knapsack_objects[1:8,], W = 3500)
        expect_equal(round(dk$value), 16770)
        expect_true(all(round(dk$elements) %in% c(5, 8)))

        dk <- dynamic_knapsack(x = knapsack_objects[1:12,], W = 3500)
        expect_equal(round(dk$value), 16770)
        expect_true(all(round(dk$elements) %in% c(5, 8)))

        dk <- dynamic_knapsack(x = knapsack_objects[1:8,], W = 2000)
        expect_equal(round(dk$value), 15428)
        expect_true(all(round(dk$elements) %in% c(3, 8)))

        dk <- dynamic_knapsack(x = knapsack_objects[1:12,], W = 2000)
        expect_equal(round(dk$value), 15428)
        expect_true(all(round(dk$elements) %in% c(3, 8)))

        st <- system.time(dk <- dynamic_knapsack(x = knapsack_objects[1:16,], W = 2000))
        expect_true(as.numeric(st)[2] >= 0.00)
})