Add a test

Author: isuruf

symengine/tests/test_lambdify.py

@@ -806,3 +806,16 @@ def test_scipy():
     lmb = se.Lambdify(args, [se.exp(-x*t)/t**5], as_scipy=True)
     res = integrate.nquad(lmb, [[1, np.inf], [0, np.inf]])
     assert abs(res[0] - 0.2) < 1e-7
+
+
+@unittest.skipUnless(have_numpy, "Numpy not installed")
+def test_as_ctypes():
+    import numpy as np
+    import ctypes
+    x, y, z = se.symbols('x, y, z')
+    l = se.Lambdify([x, y, z], [x+y+z, x*y*z+1])
+    addr1, addr2 = l.as_ctypes()
+    inp = np.array([1,2,3], dtype=np.double)
+    out = np.array([0, 0], dtype=np.double)
+    addr1(out.ctypes.data_as(ctypes.POINTER(ctypes.c_double)), inp.ctypes.data_as(ctypes.POINTER(ctypes.c_double)), addr2)
+    assert np.all(out == [6, 7])