BF: SeedCoherenceAnalyze inherits from object.

See discussion here:
http://mail.scipy.org/pipermail/nipy-devel/2011-July/006551.html

2 files changed, 29 insertions, 5 deletions

diff --git a/nitime/analysis/coherence.py b/nitime/analysis/coherence.py
index 9b7646c..60ee2d6 100644
--- a/nitime/analysis/coherence.py
+++ b/nitime/analysis/coherence.py
@@ -515,7 +515,7 @@ class SparseCoherenceAnalyzer(BaseAnalyzer):
         return freqs[lb_idx:ub_idx]
 
 
-class SeedCoherenceAnalyzer(BaseAnalyzer):
+class SeedCoherenceAnalyzer(object):
     """
     This analyzer takes two time-series. The first is designated as a
     time-series of seeds. The other is designated as a time-series of targets.
@@ -556,11 +556,15 @@ class SeedCoherenceAnalyzer(BaseAnalyzer):
 
         """
 
-        BaseAnalyzer.__init__(self, seed_time_series)
-
         self.seed = seed_time_series
         self.target = target_time_series
 
+        # Check that the seed and the target have the same sampling rate:
+        if self.seed.sampling_rate != self.target.sampling_rate:
+            e_s = "The sampling rate for the seed time-series and the target"
+            e_s += " time-series need to be identical."
+            raise ValueError(e_s)
+        
         #Set the variables for spectral estimation (can also be entered by
         #user):
         if method is None:
@@ -595,7 +599,8 @@ class SeedCoherenceAnalyzer(BaseAnalyzer):
         """Get the central frequencies for the frequency bands, given the
            method of estimating the spectrum """
 
-        self.method['Fs'] = self.method.get('Fs', self.input.sampling_rate)
+        # Get the sampling rate from the seed time-series:
+        self.method['Fs'] = self.method.get('Fs', self.seed.sampling_rate)
         NFFT = self.method.get('NFFT', 64)
         Fs = self.method.get('Fs')
         freqs = tsu.get_freqs(Fs, NFFT)
diff --git a/nitime/analysis/tests/test_coherence.py b/nitime/analysis/tests/test_coherence.py
index 6620dd1..d5691d4 100644
--- a/nitime/analysis/tests/test_coherence.py
+++ b/nitime/analysis/tests/test_coherence.py
@@ -137,5 +137,24 @@ def test_SeedCoherenceAnalyzer():
             npt.assert_almost_equal(C1.delay[0, 1], C2.delay[1])
 
         else:
-            npt.assert_raises(ValueError,nta.SeedCoherenceAnalyzer, T_seed1,
+            npt.assert_raises(ValueError, nta.SeedCoherenceAnalyzer, T_seed1,
                               T_target, this_method)
+
+def test_SeedCoherenceAnalyzer_same_Fs():
+    """
+    
+    Providing two time-series with different sampling rates throws an error
+    
+    """ 
+
+    Fs1 = np.pi
+    Fs2 = 2 * np.pi
+    t = np.arange(256)
+    
+    T1 = ts.TimeSeries(np.random.rand(t.shape[-1]),
+                       sampling_rate=Fs1)
+ 
+    T2 = ts.TimeSeries(np.random.rand(t.shape[-1]),
+                       sampling_rate=Fs2)
+    
+    npt.assert_raises(ValueError, nta.SeedCoherenceAnalyzer, T1, T2)