tests/testthat/test-correlation_threshold.R

In cytomining/cytominer: Methods for Image-Based Cell Profiling

context("correlation_threshold")

test_that(
  "`correlation_threshold` selects variables that are not highly correlated",
  {
    set.seed(123)
    data <- data.frame(x = rnorm(30))
    data$y <- rnorm(30) / 1000
    data$z <- data$x + rnorm(30) / 1000

    db <- DBI::dbConnect(RSQLite::SQLite(), ":memory:")

    data <- dplyr::copy_to(db, data)

    expect_equal(
      correlation_threshold(
        variables = c("x", "y", "z"),
        sample = data %>% dplyr::collect()
      ),
      c("z")
    )

    expect_equal(
      correlation_threshold(
        variables = c("x", "y"),
        sample = data %>% dplyr::collect()
      ),
      character(0)
    )

    DBI::dbDisconnect(db)
  }
)