Convert Array<A, D> into ArrayBase<S, D>

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Assessment

Difficulty
5/5
Estimated time
Over a week
Newbie friendliness
25/100
Issue type
Feature
Clarity
Mostly clear
Activity status
Stale
Tech stack
rust
Domain
data

Research direction

Start by reading Array, ArrayBase, into_owned, and into_shared, then review the strongly typed strides discussion in issue #283. Determine whether an owned array can be generalized to ArrayBase without copying while preserving its strides, with results usable as both Array and RcArray.

Written by the indexing model from the issue text.

Description

enhancement

I would like to switch array type to implement a general library

pub fn algorithm<A, Si, So, D>(a: ArrayBase<Si, D>) -> ArrayBase<So, D>
where Si: Data<Elem = A>, So: DataOwned<Elem =A>, D: Dimension
{ ... }

Users of this library can get the result using both Array and RcArray:

let result1: Array2<f64> = algorithm(a);
let result2: RcArray2<f64> = algorithm(a);

However, some algorithm in this crate (e.g. ndarray::linalg::Dot::dot) returns Array,
and thus I try to write a function that convert Array<D> into ArrayBase<S: DataOwned, D> without data copy:

fn generalize<A, S, D>(a: Array<A, D>) -> ArrayBase<S, D>
where
  S: DataOwned<Elem =A>,
  D: Dimension,
{
  ArrayBase::from_shape_vec(a.dim(), a.into_raw_vec())
}

This is an generalization of into_owned and into_shared. This generalize can be compiled, but does not keep its stride.

let a: Array3<f64> = Array::zeros((3, 2, 4).f()); // f-order
let ans = a.clone();
let a: Array3<f64> = generalize(a); // c-order
assert_eq!(a, ans); /// panic!

I cannot find a way to keep strides :< I suspect that I need the strongly typed strides #283
Is it possible to implement it correctly out of this crate? If impossible, please add such function.

Dominant language
Rust
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