Merge pull request #6 from AUAS-Pulsar/ffttest

added FFT tests

Author: TVH7

.coverage

@@ -19,6 +19,7 @@ script:
   - pylint *.py
   - coverage run -a tests/test_filterbank.py
   - coverage run -a tests/test_header.py
+  - coverage run -a tests/test_fft.py
 
 after_success:
   - codecov

.travis.yml

@@ -1,26 +1,68 @@
+"""
+    fourier.py test
+"""
+
 import unittest
 import numpy as np
 
 from context import fourier
 
-def fft1(x):
-    L = len(x)
+def fft1(test_input):
+    """
+        A simple fft implementation. 
+        This is the same function with which numpy tests their FFT funciton.
+    """
+    L = len(test_input)
     phase = -2j*np.pi*(np.arange(L)/float(L))
     phase = np.arange(L).reshape(-1, 1) * phase
-    return np.sum(x*np.exp(phase), axis=1)
+    return np.sum(test_input*np.exp(phase), axis=1)
 
 class TestFft(unittest.TestCase):
     """
         Testclass for testing fourier transforms
     """
 
     def test_dft(self):
-        x = np.random.random(30) + 1j*np.random.random(30)
-        self.assertAlmostEqual(fft1(x), fourier.DFT_slow(x))
+        """
+            Test for DFT function
+        """
+        test_input = np.random.random(32) + 1j*np.random.random(32)
+        test_input = np.asarray(test_input)
+        self.assertAlmostEqual(fft1(test_input).all(), fourier.DFT_slow(test_input).all())
+
 
     def test_fft(self):
-        x = np.random.random(30) + 1j*np.random.random(30)
-        self.assertAlmostEqual(fft1(x), fourier.FFT_vectorized(x))
+        """
+            Test for FFT_vectorized function
+        """
+        test_input = np.random.random(32) + 1j*np.random.random(32)
+        test_input = np.asarray(test_input)
+        self.assertAlmostEqual(fft1(test_input).all(), fourier.FFT_vectorized(test_input).all())
+
+
+    def test_wrong_array_size(self):
+        """
+            Tests for correct input for the FFT_vectorized function. 
+            Fails if the input is not a power of 2.
+        """
+        test_input = np.random.random(30) + 1j*np.random.random(30)
+        with self.assertRaises(ValueError):
+            fourier.FFT_vectorized(test_input)
+
+
+    def test_fftfreq(self):
+        """
+            Test for fftfreq function
+        """
+        test_input = [0, 1, 2, 3, 4, -4, -3, -2, -1]
+        test_input = np.asarray(test_input)
+        self.assertAlmostEqual(9*fourier.fftfreq(9).all(), test_input.all())
+        self.assertAlmostEqual(9*np.pi*fourier.fftfreq(9, np.pi).all(), test_input.all())
+        test_input = [0, 1, 2, 3, 4, -5, -4, -3, -2, -1]
+        test_input = np.asarray(test_input)
+        self.assertAlmostEqual(10*fourier.fftfreq(10).all(), test_input.all())
+        self.assertAlmostEqual(10*np.pi*fourier.fftfreq(10, np.pi).all(), test_input.all())
+
 
 if __name__ == '__main__':
     unittest.main()

tests/test_fft.py

@@ -0,0 +1,12 @@
+import unittest
+import numpy as np
+
+from context import plot
+
+class TestPlot(unittest.TestCase):
+    """
+        Testclass for testing the plot class
+    """
+
+    def test_psd(self):
+