Function solve 

pub fn solve<F, M>(
    mapping: &mut M,
    start: &[F],
    first: &[F],
    options: &Options<'_, F>,
) -> Result<Found<Vec<F>, F>, <M as Mapping<F>>::Error>
where
    F: Native + Factor,
    M: Mapping<F>,

A zero of mapping from start, by the method Options::method_for gives. first holds mapping’s values at start, which the caller computes. They give the number of values, and count as the search’s first evaluation. Where mapping gives more values than it has variables, the result is the least-squares solution, and where it gives fewer, a nearby solution.

Panics

If Options::check rejects the options.