diff --git a/postpic/datahandling.py b/postpic/datahandling.py
index 6d63a53..0b1b9a8 100644
--- a/postpic/datahandling.py
+++ b/postpic/datahandling.py
@@ -1742,7 +1742,7 @@ def _integrate_constant(self, axes):
     def _integrate_scipy(self, axes, method):
         ret = copy.copy(self)
         for axis in reversed(sorted(axes)):
-            ret._matrix = method(ret, ret.axes[axis].grid, axis=axis)
+            ret._matrix = method(ret, x=ret.axes[axis].grid, axis=axis)
             del ret.axes[axis]
             del ret.axes_transform_state[axis]
             del ret.transformed_axes_origins[axis]
@@ -1787,7 +1787,7 @@ def _integrate_fast(self, axes):
 
         return ret
 
-    def integrate(self, axes=None, method=scipy.integrate.simps):
+    def integrate(self, axes=None, method=scipy.integrate.simpson):
         '''
         Calculates the definite integral along the given axes.
 
diff --git a/test/test_datahandling.py b/test/test_datahandling.py
index e0428a9..bbdb25b 100755
--- a/test/test_datahandling.py
+++ b/test/test_datahandling.py
@@ -612,8 +612,8 @@ def test_integrate(self):
         print('type(a.matrix)', type(a.matrix))
         self.assertTrue(np.isclose(a, b))
 
-        b = self.f2d_fine.integrate(method=scipy.integrate.simps)
-        c = self.f2d_fine.integrate(method=scipy.integrate.trapz)
+        b = self.f2d_fine.integrate(method=scipy.integrate.simpson)
+        c = self.f2d_fine.integrate(method=scipy.integrate.trapezoid)
 
         self.assertTrue(np.isclose(b, 0))
         self.assertTrue(np.isclose(c, 0))