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// Copyright (c) 2015, Mikhail Vorotilov
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are met:
//
// * Redistributions of source code must retain the above copyright notice, this
//   list of conditions and the following disclaimer.
//
// * Redistributions in binary form must reproduce the above copyright notice,
//   this list of conditions and the following disclaimer in the documentation
//   and/or other materials provided with the distribution.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
// DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
// FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
// DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
// SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
// CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
// OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

use super::FloatType;

/// Possible errors
#[derive(Debug,PartialEq)]
pub enum SearchError {
    /// The algorithm could converge within the given number of iterations
    NoConvergency,
    /// Initial values do not bracket zero
    NoBracketing,
    /// The algorithm cannot continue from the point where the derivative is zero
    ZeroDerivative, /* /// The algorithm is not yet implemented
                     * NotImplemented, */
}

/// The way to check if the algorithm has finished by either finding a root
/// or reaching the iteration limit.
pub trait Convergency<F: FloatType> {
    /// Return true if the given Y value is close enough to the zero
    fn is_root_found(&self, y: F) -> bool;
    /// Return true if given x values are close enough to each other
    fn is_converged(&self, x1: F, x2: F) -> bool;
    /// Return true if no more iterations desired
    fn is_iteration_limit_reached(&self, iter: usize) -> bool;
}

pub mod newton_raphson;
pub mod brent;
pub mod secant;
pub mod regula_falsi;

pub mod simple_convergency;
pub mod debug_convergency;