 b/tests/limma/test_fitFDist.py
+import unittest
+import numpy as np
+from inmoose.limma.fitFDist import trigammaInverse
+class Test(unittest.TestCase):
+    def test_trigammainverse(self):
+        res = trigammaInverse(np.array([np.nan, 0, 1e8, -1, 5]))
+        self.assertTrue(
+            np.allclose(
+                res,
+                [np.nan, np.inf, 0.0001000, np.nan, 0.4961687],
+                equal_nan=True,
+                atol=1e-5,
+            )
+        )