plot_objective_functions.py 文件源码

def plot_3d(objective_function, length=20):
    """
    Plot 3D functions

    :param objective_function:
    :type objective_function:
    :param length:
    :type length:
    :return:
    :rtype:
    """
    bounds = objective_function.get_bounds()

    if len(bounds) != 2:
        return

    x_grid = np.linspace(bounds[0][0], bounds[0][1], length)
    y_grid = np.linspace(bounds[1][0], bounds[1][1], length)
    x_grid, y_grid = np.meshgrid(x_grid, y_grid)
    grid = np.vstack((x_grid.flatten(), y_grid.flatten())).T
    z_points = objective_function.evaluate(grid)
    z_points = z_points.reshape(length, length)

    fig = pyplot.figure()
    axis = fig.gca(projection='3d')

    surf = axis.plot_surface(x_grid, y_grid,
                             z_points, rstride=1, cstride=1,
                             cmap=cm.cool, linewidth=0, antialiased=False,
                             alpha=0.3)
    axis.contour(x_grid.tolist(), y_grid.tolist(), z_points.tolist(),
                 zdir='z', offset=z_points.min(), cmap=cm.cool)

    axis.set_xlim(bounds[0][0], bounds[0][1])
    axis.set_ylim(bounds[1][0], bounds[1][1])
    pyplot.title(objective_function.__class__.__name__)
    axis.zaxis.set_major_locator(LinearLocator(10))
    axis.zaxis.set_major_formatter(FormatStrFormatter('%.02f'))
    fig.colorbar(surf, shrink=0.5, aspect=5)

    pyplot.show()