Merge pull request scipy#8183 from endolith/0d_conj_correlate

FIX: 0d conj correlate

scipy/signal/signaltools.py

@@ -212,7 +212,7 @@ def correlate(in1, in2, mode='full', method='auto'):
     in2 = asarray(in2)
 
     if in1.ndim == in2.ndim == 0:
-        return in1 * in2
+        return in1 * in2.conj()
     elif in1.ndim != in2.ndim:
         raise ValueError("in1 and in2 should have the same dimensionality")
 
@@ -1112,7 +1112,7 @@ def correlate2d(in1, in2, mode='full', boundary='fill', fillvalue=0):
 
     val = _valfrommode(mode)
     bval = _bvalfromboundary(boundary)
-    out = sigtools._convolve2d(in1, in2, 0, val, bval, fillvalue)
+    out = sigtools._convolve2d(in1, in2.conj(), 0, val, bval, fillvalue)
 
     if swapped_inputs:
         out = out[::-1, ::-1]

scipy/signal/tests/test_signaltools.py

@@ -1385,6 +1385,24 @@ def test_rank3(self, dt):
         assert_array_almost_equal(y, y_r, decimal=self.decimal(dt) - 1)
         assert_equal(y.dtype, dt)
 
+    def test_rank0(self, dt):
+        a = np.array(np.random.randn()).astype(dt)
+        a += 1j * np.array(np.random.randn()).astype(dt)
+        b = np.array(np.random.randn()).astype(dt)
+        b += 1j * np.array(np.random.randn()).astype(dt)
+
+        y_r = (correlate(a.real, b.real)
+               + correlate(a.imag, b.imag)).astype(dt)
+        y_r += 1j * (-correlate(a.real, b.imag) + correlate(a.imag, b.real))
+
+        y = correlate(a, b, 'full')
+        assert_array_almost_equal(y, y_r, decimal=self.decimal(dt) - 1)
+        assert_equal(y.dtype, dt)
+
+        assert_equal(correlate([1], [2j]), correlate(1, 2j))
+        assert_equal(correlate([2j], [3j]), correlate(2j, 3j))
+        assert_equal(correlate([3j], [4]), correlate(3j, 4))
+
 
 class TestCorrelate2d(object):
 
@@ -1419,6 +1437,11 @@ def test_invalid_shapes(self):
         assert_raises(ValueError, signal.correlate2d, *(a, b), **{'mode': 'valid'})
         assert_raises(ValueError, signal.correlate2d, *(b, a), **{'mode': 'valid'})
 
+    def test_complex_input(self):
+        assert_equal(signal.correlate2d([[1]], [[2j]]), -2j)
+        assert_equal(signal.correlate2d([[2j]], [[3j]]), 6)
+        assert_equal(signal.correlate2d([[3j]], [[4]]), 12j)
+
 
 class TestLFilterZI(object):