How to extract arrays from a Python object?

[zmitchell]

If I have a Python dictionary (i.e. a PyDict), and I call get_item on it I get back a &PyAny. How do I go about converting this to a PyArray?

All of the documentation contains examples where NumPy arrays are passed directly to the Rust extension, but I haven't seen any where they are attributes of a class or stored as a reference, in other words when there is a layer of indirection between the NumPy array and the Rust extension. I would be glad to submit an example once I know how to do this.

[adamreichold]

I would expect that you would be able to downcast the &PyAny returned by get_item into the array type, e.g.

fn array_in_dict(dict: &PyDict) {
    let array = dict
        .get_item(42)
        .unwrap()
        .downcast::<PyArray2<f64>>()
        .unwrap();

    ...
}