peroxide 0.30.11

#[macro_use]
extern crate peroxide;
use peroxide::fuga::*;

fn main() {
    let init_state = State::<f64>::new(0f64, c!(1), c!(0));

    let mut ode_solver = ExplicitODE::new(test_fn);

    ode_solver
        .set_method(ExMethod::RK4)
        .set_initial_condition(init_state)
        .set_step_size(0.01)
        .set_times(1000);

    let _result = ode_solver.integrate();

    // let mut st = SimpleWriter::new();
    // st.set_path("example_data/rk4_test.pickle")
    //     .insert_matrix(result)
    //     .write_pickle();
}

fn test_fn(st: &mut State<f64>, _: &NoEnv) {
    let x = st.param;
    let y = &st.value;
    let dy = &mut st.deriv;
    dy[0] = (5f64 * x.powi(2) - y[0]) / (x + y[0]).exp();
}