diff --git a/wetb/fatigue_tools/tests/test_fatigue.py b/wetb/fatigue_tools/tests/test_fatigue.py
index a25745e157215dc1666b40e66dee3bfb4d5247dc..2a7bfb253db90e72a582f9db3550e2c85e77ab9d 100644
--- a/wetb/fatigue_tools/tests/test_fatigue.py
+++ b/wetb/fatigue_tools/tests/test_fatigue.py
@@ -14,8 +14,8 @@ standard_library.install_aliases()
 import unittest
 
 import numpy as np
-from wetb.fatigue_tools.fatigue import eq_load, rainflow_astm, rainflow_windap, \
-    cycle_matrix
+from wetb.fatigue_tools.fatigue import (eq_load, rainflow_astm,
+                                        rainflow_windap, cycle_matrix)
 from wetb.hawc2 import Hawc2io
 import os
 
@@ -31,28 +31,50 @@ class TestFatigueTools(unittest.TestCase):
         m = 1
         point_per_deg = 100
 
-        # sine signal with 10 periods (20 peaks)
+        for amplitude in [1,2,3]:
+            peak2peak = amplitude * 2
+            # sine signal with 10 periods (20 peaks)
+            nr_periods = 10
+            time = np.linspace(0, nr_periods*2*np.pi, point_per_deg*180)
+            neq = time[-1]
+            # mean value of the signal shouldn't matter
+            signal = amplitude * np.sin(time) + 5
+            r_eq_1hz = eq_load(signal, no_bins=1, m=m, neq=neq)[0]
+            r_eq_1hz_expected = ((2*nr_periods*amplitude**m)/neq)**(1/m)
+            np.testing.assert_allclose(r_eq_1hz, r_eq_1hz_expected)
+
+            # sine signal with 20 periods (40 peaks)
+            nr_periods = 20
+            time = np.linspace(0, nr_periods*2*np.pi, point_per_deg*180)
+            neq = time[-1]
+            # mean value of the signal shouldn't matter
+            signal = amplitude * np.sin(time) + 9
+            r_eq_1hz2 = eq_load(signal, no_bins=1, m=m, neq=neq)[0]
+            r_eq_1hz_expected2 = ((2*nr_periods*amplitude**m)/neq)**(1/m)
+            np.testing.assert_allclose(r_eq_1hz2, r_eq_1hz_expected2)
+
+            # 1hz equivalent should be independent of the length of the signal
+            np.testing.assert_allclose(r_eq_1hz, r_eq_1hz2)
+
+    def test_rainflow_combi(self):
+        """Signal with two frequencies and amplitudes
+        """
+
+        amplitude = 1
+        # peak2peak = amplitude * 2
+        m = 1
+        point_per_deg = 100
+
         nr_periods = 10
         time = np.linspace(0, nr_periods*2*np.pi, point_per_deg*180)
-        neq = time[-1]
-        # mean value of the signal shouldn't matter
-        signal = amplitude * np.sin(time) + 5
-        r_eq_1hz = eq_load(signal, no_bins=1, m=m, neq=neq)[0]
-        r_eq_1hz_expected = ((2*nr_periods*amplitude**m)/neq)**(1/m)
-        np.testing.assert_allclose(r_eq_1hz, r_eq_1hz_expected)
-
-        # sine signal with 20 periods (40 peaks)
-        nr_periods = 20
-        time = np.linspace(0, nr_periods*2*np.pi, point_per_deg*180)
-        neq = time[-1]
-        # mean value of the signal shouldn't matter
-        signal = amplitude * np.sin(time) + 9
-        r_eq_1hz2 = eq_load(signal, no_bins=1, m=m, neq=neq)[0]
-        r_eq_1hz_expected2 = ((2*nr_periods*amplitude**m)/neq)**(1/m)
-        np.testing.assert_allclose(r_eq_1hz2, r_eq_1hz_expected2)
-
-        # 1hz equivalent load should be independent of the length of the signal
-        np.testing.assert_allclose(r_eq_1hz, r_eq_1hz2)
+
+        signal = (amplitude*np.sin(time)) + 5 + (amplitude*0.2*np.cos(5*time))
+        cycles, ampl_bin_mean, ampl_edges, mean_bin_mean, mean_edges = \
+            cycle_matrix(signal, ampl_bins=10, mean_bins=5)
+
+        cycles.sum()
+
+
 
     def test_astm1(self):