Avoid dependency on specific version of ndarray

[wangjia184]

First of all, thank you for your great work on powerboxesrs — it’s very useful!

I wanted to share a suggestion regarding the function APIs. Currently, many function parameters depend directly on the ndarray crate types. This tight coupling means that users must depend on the exact same ndarray version to avoid compilation conflicts, which can be quite limiting in real projects with multiple dependencies.

Take this method as an example, https://docs.rs/powerboxesrs/latest/powerboxesrs/nms/fn.nms.html

pub fn nms<'a, N, BA, SA>(
    boxes: BA,
    scores: SA,
    iou_threshold: f64,
    score_threshold: f64,
) -> Vec<usize>
where
    N: Num + PartialEq + PartialOrd + ToPrimitive + Copy + PartialEq + 'a,
    BA: Into<ArrayView2<'a, N>>,
    SA: Into<ArrayView1<'a, f64>>,

BA: Into<ArrayView2<'a, N>> means I have to use the exact version of ndarray.

Would it be possible to provide alternative overloads or versions of these functions that accept raw slices like &[f32] (using unsafe if needed)? This could help significantly reduce version conflicts and make the library easier to integrate. Alternatively, any other approaches you might recommend to decouple the API from a specific ndarray version would also be appreciated.

[Smirkey]

Sure! Let me have a look !