Dear Colleagues,

I'm trying to run the example from http://www.dolfin-adjoint.org/en/latest/documentation/mpec/mpec.html using firedrake_adjoint (see the attached code) but I get the below error message.

I appreciate your help. Thank you.

Regards

---------------------------------------------------------------------------
TypeError Traceback (most recent call last)
<ipython-input-8-1a7944c0c864> in <module>
40 ic.update(y_opt)
41
---> 42 alpha.assign(float(alpha) / 2)
43 print("Set alpha to %f." % float(alpha))

~/opt/Computational_venv/src/firedrake/firedrake/adjoint/constant.py in wrapper(self, *args, **kwargs)
34 other = args[0]
35 if not isinstance(other, OverloadedType):
---> 36 other = create_overloaded_object(ndarray(other))
37
38 block = ConstantAssignBlock(self, other)

TypeError: 'float' object cannot be interpreted as an integer