diff --git a/src/util/Util.test.js b/src/util/Util.test.js
index d7b09bc..9ffaa25 100644
--- a/src/util/Util.test.js
+++ b/src/util/Util.test.js
@@ -1,7 +1,113 @@
 import assert from "assert";
-import { isNumeric } from "./Util.js";
+import { isNumeric, randint, round, sum, toNumerical, turnSquareBracketsIntoArrays } from "./Util.js";
 
-assert(isNumeric("1.2"))
-assert(isNumeric(0))
-assert(!isNumeric("NaN"))
-assert(!isNumeric("hey"))
+assert(isNumeric("1.2"));
+assert(isNumeric(0));
+assert(!isNumeric("NaN"));
+assert(!isNumeric("hey"));
+
+// number -> number, e.g. 2 -> 2
+assert.equal(2, toNumerical(2));
+
+// [number] -> [number], e.g. [1,2,3] -> [1,2,3]
+assert.deepEqual([1, 2, 3], toNumerical([1, 2, 3]));
+assert(Array.isArray(toNumerical([0])));
+
+// numeral string -> number, e.g. "8" -> 8
+assert.deepEqual(8, toNumerical("8"));
+
+// [number | numeral string] -> [number], e.g. [1, 2, "3"] -> [1,2,3]
+assert.deepEqual([1, 2, 3], toNumerical([1, 2, "3"]));
+
+// Establish what happens when fed an array-like string
+assert.deepEqual([1, 2, 3], toNumerical(...turnSquareBracketsIntoArrays("[1, 2, 3][]]", 2)));
+
+// Throws
+(async () =>
+{
+	await assert.rejects(
+		async () =>
+		{
+			toNumerical(turnSquareBracketsIntoArrays([1, 2]));
+		},
+		{
+			origin: "util.toNumerical",
+			context: "when converting an object to its numerical form",
+			error: "unable to convert undefined to a number",
+		},
+	);
+})();
+
+// Towards a NumPy inspired bound random integer producer
+for (let i = 0; i < 100; i += 1)
+{
+	// Calling sans arguments gives back zero no matter what
+	assert.equal(randint(), 0);
+}
+
+for (let i = 0; i < 100; i += 1)
+{
+	// Same when calling with a min of one sans max
+	assert.equal(randint(1), 0);
+}
+
+// Expect min to be zero, max to be one, result to be zero
+assert(randint(1) >= 0 === randint(1) < 1);
+
+// Same when calling with a min of one sans max
+assert.equal(randint(1), 0);
+
+for (let i = 0; i < 100; i += 1)
+{
+	// Same with null
+	assert.equal(randint(null), 0);
+}
+
+for (let i = 100; i > 0; i -= 1)
+{
+	// Try out a few ranges in the positive
+	assert(randint(i) < i);
+}
+
+for (let i = -99; i < 0; i += 1)
+{
+	// What happens when using negative parameters?
+	assert(randint(2 * i, i) <= i);
+}
+
+try
+{
+	randint(0, -10);
+}
+catch ({ error })
+{
+	assert.equal(error, "min should be <= max");
+}
+
+// Implement Crib Sheet math extras
+// These are taken from the SO question above
+// https://stackoverflow.com/questions/11832914
+const actual = [
+	10,
+	1.7777777,
+	9.1,
+];
+
+const expected = [
+	10,
+	1.78,
+	9.1,
+];
+
+const got = actual.map((input) => round(input, 2));
+
+assert.deepEqual(expected, got);
+
+assert.equal(sum(null), 0);
+assert.equal(sum(), 0);
+assert(!sum([0]));
+assert.equal(sum([1, NaN, null, undefined]), 1);
+assert.equal(sum([1, 2, -3]), 0);
+
+// Careful Thomas!
+assert.equal(sum(["a1", 2]), 2);