pub unsafe trait Element: Clone + Send {
const IS_COPY: bool;
fn get_dtype(py: Python<'_>) -> &PyArrayDescr;
}Expand description
Represents that a type can be an element of PyArray.
Currently, only integer/float/complex/object types are supported. The NumPy documentation list the other built-in types which we are not yet implemented.
Safety
A type T that implements this trait should be safe when managed by a NumPy
array, thus implementing this trait is marked unsafe. Data types that don’t
contain Python objects (i.e., either the object type itself or record types
containing object-type fields) are assumed to be trivially copyable, which
is reflected in the IS_COPY flag. Furthermore, it is assumed that for
the object type the elements are pointers into the Python heap and that the
corresponding Clone implemenation will never panic as it only increases
the reference count.
Custom element types
Note that we cannot safely store Py<T> where T: PyClass, because the type information would be
eliminated in the resulting NumPy array.
In other words, objects are always treated as Py<PyAny> (a.k.a. PyObject) by Python code,
and only Py<PyAny> can be stored in a type safe manner.
You can however create Array<Py<T>, D> and turn that into a NumPy array
safely and efficiently using from_owned_object_array.
Associated Constants
Flag that indicates whether this type is trivially copyable.
It should be set to true for all trivially copyable types (like scalar types and record/array types only containing trivially copyable fields and elements).
This flag should always be set to false for object types or record types
that contain object-type fields.
Required methods
fn get_dtype(py: Python<'_>) -> &PyArrayDescr
fn get_dtype(py: Python<'_>) -> &PyArrayDescr
Returns the associated type descriptor (“dtype”) for the given element type.