Nothing
context("Test implementation of canberra distance ...")
P <- 1:10 / sum(1:10)
Q <- 20:29 / sum(20:29)
V <- -10:10
W <- -20:0
# function to test distance matrix functionality
# for different distance measures
test_dist_matrix <- function(x, FUN) {
dist.fun <- match.fun(FUN)
res.dist.matrix <- matrix(NA_real_, nrow(x), nrow(x))
for (i in 1:nrow(x)) {
for (j in 1:nrow(x)) {
res.dist.matrix[i, j] <- dist.fun(x[i, ], x[j, ])
}
}
return(res.dist.matrix[lower.tri(res.dist.matrix, diag = FALSE)])
}
test_canberra_dist <- function(P, Q) {
sum(abs((P) - (Q)) / ((P) + (Q)))
}
test_that("distance(method = 'canberra') computes the correct distance value.",
{
expect_equal(as.vector(philentropy::distance(rbind(P, Q), method = "canberra")),
test_canberra_dist(P, Q))
expect_equal(as.vector(philentropy::distance(rbind(P, Q), method = "canberra")),
as.vector(stats::dist(base::rbind(P, Q), method = "canberra")))
# test correct computation of distance matrix
distMat <-
rbind(rep(0.2, 5), rep(0.1, 5), c(5, 1, 7, 9, 5))
dist.vals <-
distance(distMat, method = "canberra")
expect_equal(dist.vals[lower.tri(dist.vals, diag = FALSE)],
test_dist_matrix(distMat, FUN = test_canberra_dist))
})
test_that(
"distance(method = 'canberra') computes the correct distance value when P_i and Q_i are 0 -> 0/0 is then replaced by 0.",
{
A <- c(0, 0.25, 0.25, 0, 0.25, 0.25)
B <- c(0, 0, 0.25, 0.25, 0.25, 0.25)
canb <- function(x, y) {
dist <- vector(mode = "numeric", length = 1)
dist <- 0
for (i in 1:length(x)) {
if ((abs(x[i] - y[i]) == 0) | ((x[i] + y[i]) == 0)) {
dist = dist
} else {
dist = dist + (abs(x[i] - y[i]) / ((x[i]) + (y[i])))
}
}
return(dist)
}
expect_equal(as.vector(philentropy::distance(rbind(A, B), method = "canberra")), canb(A, B))
}
)
Any scripts or data that you put into this service are public.
Add the following code to your website.
For more information on customizing the embed code, read Embedding Snippets.