I have not yet got the overall architecture right, but the functions are

beginning to work.

test/humidity/wet_bulb_test.clj

@@ -0,0 +1,47 @@
+(ns humidity.wet-bulb-test
+  (:require [clojure.test :refer [deftest is testing]]
+            [humidity.wet-bulb :refer [wet-bulb-temperature]]))
+
+
+(deftest wet-bulb-test
+  (testing "Example from paper"
+    (let [expected 13.7
+          temperature 20
+          rel-humidity 50
+          actual (wet-bulb-temperature temperature rel-humidity)]
+      (println (format "Expected: %s; actual: %s" expected actual))
+      (is (< (abs (- expected actual)) 0.001))))
+
+  (testing "Interpolations from graph"
+    (let [min-expected 31
+          max-expected 33
+          temperature 37
+          rel-humidity 70
+          actual (wet-bulb-temperature temperature rel-humidity)]
+      (println (format "Expected: %s...%s; actual: %s" min-expected max-expected actual))
+      (is (< min-expected actual max-expected)))
+
+    (let [min-expected 34
+          max-expected 36
+          temperature 39.7
+          rel-humidity 70
+          actual (wet-bulb-temperature temperature rel-humidity)]
+      (println (format "Expected: %s...%s; actual: %s" min-expected max-expected actual))
+      (is (< min-expected actual max-expected)))
+
+
+    (let [min-expected 31
+          max-expected 34
+          temperature 40
+          rel-humidity 60
+          actual (wet-bulb-temperature temperature rel-humidity)]
+      (println (format "Expected: %s...%s; actual: %s" min-expected max-expected actual))
+      (is (< min-expected actual max-expected)))
+
+    (let [min-expected 32
+          max-expected 35
+          temperature 51
+          rel-humidity 30
+          actual (wet-bulb-temperature temperature rel-humidity)]
+      (println (format "Expected: %s...%s; actual: %s" min-expected max-expected actual))
+      (is (< min-expected actual max-expected)))))