[contrasting] add aic test in abstract_gev_trend_test.py

extreme_trend/abstract_gev_trend_test.py

 from math import ceil, floor
+import numpy.testing as npt
 
 import matplotlib.pyplot as plt
 import numpy as np
@@ -113,7 +114,9 @@ class AbstractGevTrendTest(object):
     @property
     def aic(self):
         aic = 2 * self.total_number_of_parameters_for_unconstrained_model + self.unconstrained_model_deviance
-        assert np.equal(self.unconstrained_estimator.result_from_model_fit.aic, aic)
+        assert np.equal(self.total_number_of_parameters_for_unconstrained_model, self.unconstrained_estimator.margin_model.nb_params)
+        npt.assert_almost_equal(self.unconstrained_estimator.result_from_model_fit.aic, aic, decimal=12)
+        npt.assert_almost_equal(self.unconstrained_estimator.aic(), aic, decimal=12)
         return aic
 
     @property