如何在MATLAB中绘制带电环的电场？

% 定义带电环的参数
radius = 1; % 环的半径
charge = 1; % 环上每个电荷的电荷量
num_charges = 100; % 环上电荷的数量

% 创建网格
x = linspace(-2, 2, 100);
y = linspace(-2, 2, 100);
[X, Y] = meshgrid(x, y);

% 计算电场
Ex = zeros(size(X));
Ey = zeros(size(Y));
for i = 1:num_charges
    theta = 2*pi*i/num_charges;
    x_charge = radius*cos(theta);
    y_charge = radius*sin(theta);
    r = sqrt((X-x_charge).^2 + (Y-y_charge).^2);
    Ex = Ex + charge*(X-x_charge)./r.^3;
    Ey = Ey + charge*(Y-y_charge)./r.^3;
end

% 绘制电场矢量
figure;
quiver(X, Y, Ex, Ey);
hold on;

% 绘制带电环
theta = linspace(0, 2*pi, 100);
x_ring = radius*cos(theta);
y_ring = radius*sin(theta);
plot(x_ring, y_ring, 'r', 'LineWidth', 2);

% 设置图形属性
axis equal;
xlabel('X');
ylabel('Y');
title('Electric Field of a Charged Ring');

% 显示图形
hold off;