Maintenance in preparation of improvements

- Switch vignette to html
- Switch tests to testthat
- NEWS.md instead of ChangeLog
- Remove names of y in lists returned by lod and loq

1 files changed, 33 insertions, 0 deletions

diff --git a/tests/testthat/test_din32645.R b/tests/testthat/test_din32645.R
new file mode 100644
index 0000000..e6d2840
--- /dev/null
+++ b/tests/testthat/test_din32645.R
@@ -0,0 +1,33 @@
+context("Known results for the dataset provided in DIN 32645")
+
+require(chemCal)
+
+m <- lm(y ~ x, data = din32645)
+prediction <- inverse.predict(m, 3500, alpha = 0.01)
+
+test_that("We get correct confidence intervals", {
+  # Result collected from Procontrol 3.1 (isomehr GmbH)
+  expect_equal(round(prediction$Confidence, 5), 0.07434)
+})
+
+test_that("We get a correct critical value", {
+  crit <- lod(m, alpha = 0.01, beta = 0.5)
+  # DIN 32645 gives 0.07 for the critical value
+  # (decision limit, "Nachweisgrenze")
+  expect_equal(round(crit$x, 2), 0.07)
+  # According to Dintest test data, we should get 0.0698
+  expect_equal(round(crit$x, 4), 0.0698)
+})
+
+test_that("We get a correct smalles detectable value using the DIN method", {
+  lod.din <- lod(m, alpha = 0.01, beta = 0.01, method = "din")
+  # DIN 32645 gives 0.14 for the smallest detectable value ("Erfassungsgrenze")
+  expect_equal(round(lod.din$x, 2), 0.14)
+})
+
+test_that("We get a correct limit of quantification", {
+  loq.din <- loq(m, alpha = 0.01)
+  # The value cited for Procontrol 3.1 (0.2121) deviates
+  # at the last digit, so we only test for three digits
+  expect_equal(round(loq.din$x, 3), 0.212)
+})