rusoda 0.1.0

Pure rust and just need log dependencies implementation of odepack dlsoda.
Documentation 
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/// Calculate dot product of 2 vectors(the first element of vector will not used).
/// # Examples
///
/// '''
/// let n = 1000;
/// let dx = vec![2.0; n + 1];
/// let dy = vec![2.0; n + 1];
/// let dot = ddot(n, &dx, &dy, 0, 0);
/// assert_eq!(4000.0, dot);
#[no_mangle]
#[inline(always)]
pub fn ddot(n: usize, dx: &[f64], dy: &[f64], incx: usize, incy: usize) -> f64 {
    let mut r = 0f64;
    let m: usize;
    let mut ix: usize;
    let mut iy: usize;

    if incx == 0 && incy == 0 {
        m = n % 5;
        if m != 0 {
            for i in 1..m + 1 {
                r += dx[i] * dy[i];
            }
            if n < 5 {
                return r;
            }
        }

        for i in (m + 1..n + 1).step_by(5) {
            r += dx[i] * dy[i]
                + dx[i + 1] * dy[i + 1]
                + dx[i + 2] * dy[i + 2]
                + dx[i + 3] * dy[i + 3]
                + dx[i + 4] * dy[i + 4]
        }
    } else {
        ix = 1;
        iy = 1;
        for _ in 1..n + 1 {
            r += dx[ix] * dy[iy];
            ix += incx;
            iy += incy;
        }
    }
    r
}