added test_first_order.py

wetb/signal_tools/tests/test_first_order.py

+'''
+Created on 13. jan. 2017
+
+@author: mmpe
+'''
+import unittest
+from wetb.signal_tools.filters import first_order
+import numpy as np
+
+class Test_first_order_filters(unittest.TestCase):
+
+
+    def test_low_pass(self):
+        a = np.random.randint(0,100,100).astype(np.float)
+        b = first_order.low_pass(a, 1, 1)
+        self.assertLess(b.std(), a.std())
+        if 0:
+            import matplotlib.pyplot as plt
+            plt.plot(a)
+            plt.plot(b)
+            plt.show()
+
+    def test_high_pass(self):
+        a = np.random.randint(0,100,100).astype(np.float)
+        b = first_order.high_pass(a, 1, 1)
+        self.assertLess(b.mean(), a.mean())
+        if 1:
+            import matplotlib.pyplot as plt
+            plt.plot(a)
+            plt.plot(b)
+            plt.show()
+if __name__ == "__main__":
+    #import sys;sys.argv = ['', 'Test.testName']
+    unittest.main()
\ No newline at end of file