test_that("Sample", {
    data(cerrado_2classes)

    data <- sits_sample(cerrado_2classes, frac = 0.1)
    expect_true(nrow(dplyr::filter(data, label == "Cerrado")) == 40)
    expect_true(nrow(dplyr::filter(data, label == "Pasture")) == 34)

    data2 <- sits_sample(cerrado_2classes, frac = 1.3, oversample = TRUE)
    expect_true(nrow(data2) > nrow(cerrado_2classes))
})

test_that("Sample reduce imbalance", {
    # print the labels summary for a sample set
    sum_ori_samples <- summary(samples_modis_ndvi)
    # reduce the sample imbalance
    new_samples <- sits_reduce_imbalance(samples_modis_ndvi,
        n_samples_over = 200, n_samples_under = 200,
        multicores = 2
    )
    # print the labels summary for the rebalanced set
    sum_new_samples <- summary(new_samples)
    expect_true(nrow(new_samples) < nrow(samples_modis_ndvi))
    expect_true(sd(sum_new_samples[["count"]]) < sd(sum_ori_samples[["count"]]))
})