diff --git a/src/BEMEWS/test/test_01_run.py b/src/BEMEWS/test/test_01_run.py
new file mode 100644
index 0000000..f389e6f
--- /dev/null
+++ b/src/BEMEWS/test/test_01_run.py
@@ -0,0 +1,64 @@
+import unittest
+
+from astropy import units as u
+from astropy.time import Time
+from astropy.coordinates import SkyCoord, EarthLocation, AltAz
+
+from importlib import import_module
+from importlib.resources import files
+import numpy as np
+import sys
+import os
+
+import BEMEWS
+
+class TestInit(unittest.TestCase):
+
+    def test_run_no_output(self):
+        """Test run with no output data.
+        """
+        _id = BEMEWS.InputDataBEMEWS()
+
+        source = SkyCoord.from_name('Betelgeuse')
+        detector = EarthLocation.of_site('SuperK')
+        time = Time('2021-05-26 14:14:00')
+        snaltaz = source.transform_to(AltAz(obstime=time, location=detector))
+
+        _id.altitude = snaltaz.alt.deg
+        _id.azimuth = snaltaz.az.deg
+        _id.outputfilenamestem = 'out/BEMEWS:PREM'
+
+        _id.densityprofile = str(files(BEMEWS.data).joinpath('PREM.rho.dat'))
+        _id.electronfraction = str(files(BEMEWS.data).joinpath('PREM.Ye.dat'))
+
+        _id.deltam_21 = 7.69e-5
+        _id.deltam_32 = 2.43e-3
+        _id.theta12 = 34.4
+        _id.theta13 = 9
+        _id.theta23 = 45
+        _id.deltaCP = 0
+
+        _id.NE = 2
+        _id.Emin = 1
+        _id.Emax = 10
+
+        _id.outputflag = False
+        _id.ecsvformat = False
+        _id.accuracy = 1.01e-9
+        _id.stepcounterlimit = 1
+
+        Pfm = np.asarray(BEMEWS.Run(_id))
+
+        self.assertTrue(
+            np.all(
+                np.isclose(Pfm[0,0,:],
+                    np.asarray([[0.66414735, 0.31137679, 0.02447587],
+                                [0.24085689, 0.27138279, 0.48776032],
+                                [0.09499576, 0.41724042, 0.48776382]]))))
+
+        self.assertTrue(
+            np.all(
+                np.isclose(Pfm[1,0,:],
+                    np.asarray([[0.66533681, 0.31019902, 0.02446416],
+                                [0.24016784, 0.27205631, 0.48777586],
+                                [0.09449535, 0.41774467, 0.48775998]]))))