tests/testthat/test-measures.R

In geodist: Fast, Dependency-Free Geodesic Distance Calculations

test_all <- identical (Sys.getenv ("MPADGE_LOCAL"), "true")

# all measures compared against geodesic
cor_lim <- 0.9

test_that ("measures", {
    n <- 1e2
    # x <- cbind (-180 + 360 * runif (n), -90 + 180 * runif (n))
    # y <- cbind (-180 + 360 * runif (2 * n),
    #            -90 + 180 * runif (2 * n))
    x <- cbind (-10 + 20 * runif (n), -10 + 20 * runif (n))
    y <- cbind (-10 + 20 * runif (2 * n), -10 + 20 * runif (2 * n))
    colnames (x) <- colnames (y) <- c ("x", "y")
    d0_x <- geodist (x, measure = "geodesic")
    d0_xy <- geodist (x, y, measure = "geodesic")
    d0_seq <- geodist (x, measure = "geodesic", sequential = TRUE)

    measures <- c ("haversine", "vincenty", "cheap")
    for (m in measures) {

        d1_x <- geodist (x, measure = m)
        d1_xy <- geodist (x, y, measure = m)
        d1_seq <- geodist (x, measure = m, sequential = TRUE)

        expect_true (max (abs (d1_x - d0_x)) > 0)
        expect_true (max (abs (d1_xy - d0_xy)) > 0)
        expect_true (max (abs (d1_seq - d0_seq)) > 0)

        if (test_all) {

            expect_true (cor (
                as.vector (d0_x),
                as.vector (d1_x)
            ) > cor_lim)
            expect_true (cor (
                as.vector (d0_xy),
                as.vector (d1_xy)
            ) > cor_lim)
            expect_true (cor (
                as.vector (d0_seq),
                as.vector (d1_seq)
            ) > cor_lim)
        }
    }
})