Trait vpsearch::MetricSpace

pub trait MetricSpace {
    type UserData;
    type Distance: Copy + PartialOrd + Bounded + Add<Output=Self::Distance>;
    fn distance(&self,
                other: &Self,
                user_data: &Self::UserData)
                -> Self::Distance;
}

Elements you're searching for must be comparable using this trait

Associated Types

type UserData

This is used as a context for comparisons. Use () if the elements already contain all the data you need.

type Distance: Copy + PartialOrd + Bounded + Add<Output=Self::Distance>

This is a fancy way of saying it should be f32 or u32

Required Methods

fn distance(&self, other: &Self, user_data: &Self::UserData) -> Self::Distance

This function must return distance between two items that meets triangle inequality. Specifically, it can't return squared distance (you must use sqrt if you use Euclidean distance)

@param user_data Whatever you want. Passed from new_with_user_data_*()

Implementors