fn custom_result(
    result: &Matrix<f32, Dyn, Const<1>, VecStorage<f32, Dyn, Const<1>>>,
    triangles: &Vec<Elist>,
    nodes: &Vec<Nlist>,
    gradient: &LinearGradient,
    plot: &mut Plot,
) {
    let T_MAX = result.max();
    let T_MIN = result.min();

    for elem in triangles {
        let node_i = &nodes[elem.node_i - 1];
        let node_j = &nodes[elem.node_j - 1];
        let node_k = &nodes[elem.node_k - 1];

        let T1 = result[node_i.node - 1];
        let T2 = result[node_j.node - 1];
        let T3 = result[node_k.node - 1];

        let temperature = (T1 + T2 + T3) / 3.0;

        let trace = Scatter::new(
            vec![node_i.x, node_j.x, node_k.x],
            vec![node_i.y, node_j.y, node_k.y],
        )
        .x_axis("x2")
        .y_axis("y2")
        .mode(Mode::None)
        .name(temperature.to_string())
        .show_legend(false)
        .fill_color(
            gradient
                .at(interpolate(temperature, T_MIN, T_MAX))
                .to_hex_string(),
        )
        .fill(Fill::ToSelf);

        plot.add_trace(trace);
    }
}