How to pass numpy array to compiled expression member variable?

9

Thanks Kamensky!

Just to add: Using the Eigen::Ref<> template instead of py::array_t<> , pybind11 casts numpy arrays directly and also gives access to the Eigen library methods.

i.e Change npArray definition to

typedef Eigen::Ref<Eigen::VectorXd> npArray;

arr declaration to npArray arr;

and the constructor method to

test_exp(npArray a) : dolfin::Expression(), arr(a) {}

This can help in using Eigen Methods e.g arr.sum() in the eval method.

1 Like