examples: Fix DC component in Ricker source

Author: ziyiyin97

examples/seismic/source.py

@@ -274,7 +274,8 @@ def wavelet(self):
         t0 = self.t0 or 1 / self.f0
         a = self.a or 1
         r = (np.pi * self.f0 * (self.time_values - t0))
-        return a * (1-2.*r**2)*np.exp(-r**2)
+        w = a * (1-2.*r**2)*np.exp(-r**2)
+        return w - w.mean() # Remove DC component
 
 
 class GaborSource(WaveletSource):

examples/seismic/tutorials/06_elastic.ipynb

@@ -29,8 +29,8 @@ def test_resample():
 
     end = min(src_a.data.shape[0], src_c.data.shape[0])
 
-    assert np.allclose(src_a.data[:end], src_c.data[:end])
-    assert np.allclose(src_a.data[:end], src_c.data[:end])
+    assert np.allclose(src_a.data[:end], src_c.data[:end], atol=3e-6)
+    assert np.allclose(src_a.data[:end], src_c.data[:end], atol=3e-6)
 
     # Text resampling based on num
     src_d = RickerSource(name='src_d', grid=model.grid, f0=f0,
@@ -42,8 +42,8 @@ def test_resample():
     assert np.isclose(src_d._time_range.step, src_e._time_range.step)
     assert np.isclose(src_d._time_range.stop, src_e._time_range.stop)
     assert src_d._time_range.num == src_e._time_range.num
-    assert np.allclose(src_d.data, src_e.data)
-    assert np.allclose(src_d.data, src_e.data)
+    assert np.allclose(src_d.data, src_e.data, atol=3e-6)
+    assert np.allclose(src_d.data, src_e.data, atol=3e-6)
 
 
 if __name__ == "__main__":