vectors 0.3.0

Sparse & dense vectors for use in high dimensional vector spaces.
Documentation 
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// This Source Code Form is subject to the terms of the Mozilla Public
// License, v. 2.0. If a copy of the MPL was not distributed with this
// file, You can obtain one at http://mozilla.org/MPL/2.0/.

use num_traits::Num;

use arrayvec::Array;

use Dot;
use super::DenseVector;

impl<T, A> Dot for DenseVector<A>
where
    T: Copy + Num,
    A: Array<Item = T>,
{
    type Scalar = T;

    fn dot(&self, rhs: &Self) -> Self::Scalar {
        debug_assert_eq!(self.len(), rhs.len());
        let lhs_iter = self.components.iter();
        let rhs_iter = rhs.components.iter();
        lhs_iter.zip(rhs_iter).fold(T::zero(), |sum, (lhs, rhs)| {
            sum + ((*lhs) * (*rhs))
        })
    }
}


#[cfg(test)]
mod test {
    use super::*;

    use expectest::prelude::*;

    #[test]
    fn dot() {
        let subject = DenseVector::from([0.0, 0.5, 1.0, 2.0, 4.0]);
        let other = DenseVector::from([0.1, 0.2, 0.3, 0.4, 0.0]);
        let dot = subject.dot(&other);
        expect!(dot).to(be_close_to(1.2));
    }
}