math: factorial submodule

vlib/math/factorial/factorial_test.v

@@ -0,0 +1,14 @@
+import math
+import math.factorial as fact
+
+fn test_factorial() {
+	assert fact.factorial(12) == 479001600
+	assert fact.factorial(5) == 120
+	assert fact.factorial(0) == 1
+}
+
+fn test_log_factorial() {
+	assert fact.log_factorial(12) == math.log(479001600)
+	assert fact.log_factorial(5) == math.log(120)
+	assert fact.log_factorial(0) == math.log(1)
+}