x = data(:,1); y = data(:,2); % 定义柯西色散方程 f = @(coeffs, x) coeffs(1) + coeffs(2) ./ x.^2 + coeffs(3) ./ x.^4; % 定义初始系数矩阵 coeffs0 = [1,1,1]; % 进行非线性拟合 coeffs = nlinfit(x,y,f,coeffs0); % 输出结果 disp(['a = ', sprintf('%e', coeffs(1))]); disp(['b = ', sprintf('%e', coeffs(2))]); disp(['c = ', sprintf('%e', coeffs(3))]); x_fit = linspace(min(x), max(x), 1000); y_fit = f(coeffs, x_fit); % 绘制原始数据散点图和拟合曲线 figure; scatter(x, y); hold on; plot(x_fit, y_fit); xlabel('λ'); ylabel('n'); legend('原始数据', '拟合曲线');这段代码没有计算rmse,请帮我补充完整
时间: 2023-06-20 11:09:50 浏览: 136
可以通过以下代码计算出拟合曲线与原始数据之间的均方根误差(RMSE):
```matlab
y_fit = f(coeffs, x); % 计算拟合值
rmse = sqrt(mean((y - y_fit).^2)); % 计算均方根误差
disp(['RMSE = ', sprintf('%e', rmse)]); % 输出结果
```
将其添加到原有代码中:
```matlab
x = data(:,1); y = data(:,2); % 定义柯西色散方程 f = @(coeffs, x) coeffs(1) + coeffs(2) ./ x.^2 + coeffs(3) ./ x.^4; % 定义初始系数矩阵 coeffs0 = [1,1,1]; % 进行非线性拟合 coeffs = nlinfit(x,y,f,coeffs0); % 计算拟合曲线与原始数据之间的均方根误差 y_fit = f(coeffs, x); % 计算拟合值 rmse = sqrt(mean((y - y_fit).^2)); % 计算均方根误差 输出结果 disp(['a = ', sprintf('%e', coeffs(1))]); disp(['b = ', sprintf('%e', coeffs(2))]); disp(['c = ', sprintf('%e', coeffs(3))]); disp(['RMSE = ', sprintf('%e', rmse)]); % 输出结果 x_fit = linspace(min(x), max(x), 1000); y_fit = f(coeffs, x_fit); % 绘制原始数据散点图和拟合曲线 figure; scatter(x, y); hold on; plot(x_fit, y_fit); xlabel('λ'); ylabel('n'); legend('原始数据', '拟合曲线');
```
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