pub fn grid_search_2d<F>(
x_values: &[f64],
y_values: &[f64],
objective: F,
direction: ObjectiveDirection,
) -> Option<GridSearchResult2D>pub fn grid_search_2d<F>(
x_values: &[f64],
y_values: &[f64],
objective: F,
direction: ObjectiveDirection,
) -> Option<GridSearchResult2D>