Matlab 绘制阴影误差图

Matlab 绘制阴影误差图

代码如下：

clear,clc;
x = 0:10:500; 
y_true =  30*sind(x) + x/10; 
sigma = 3; 
y_measured = y_true + sigma*randn(size(x)); 
plot(x,y_true,'k','linewidth',2)
hold on
plot(x,y_measured,'color',[0.0118 0.2078 0])
ylabel( 'Y轴');xlabel('X轴');
% 绘制不确定性阴影区间
errorshade(x,y_measured,sigma,[0 1 0.7]) 
legend('真实值','测量值 \pm\sigma = 3 mV ','location','northwest')
legend box off 
axis tight 
title('好看的阴影误差图')
grid minor

errorshade 函数：

function h = errorshade(x,y,sigma,color,varargin)
%errorshade绘制阴影区域以指示高斯不确定性。
%通过生成指定颜色的RGB图像并设置透明度来作图
%% 语法规则
%  errorshade(x,y,sigma,color)
%  errorshade(...,'resolution',res)
%  errorshade(...,'average',N)
%  h = errorshade(...)
%
%% 简介
%
% %errorshade(x,y,sigma ,color)以高斯阴影区域为中心绘制
% x,y：为数据行。
%sigma：表示阴影的一个标准偏差
% color：为rgb值的三元素向量。

%% 举例
%数据
% x = 0:10:500;
% y_true =  30*sind(x) + x/10;
% sigma = 3;
% y_measured = y_true + sigma*randn(size(x));
% plot(x,y_true,'k','linewidth',2)
% hold on
% plot(x,y_measured,'color',[0.0118 0.2078 0])
% ylabel 'some values in mV'
%
% % 绘制不确定性阴影区间
% errorshade(x,y_measured,sigma,[0.0824 0.6902 0.1020])
% legend('true value','measured value \pm\sigma = 3 mV uncertainty','location','northwest')
% legend boxoff
% axis tight
%% Error checks:
narginchk(4,inf)
assert(numel(color)==3,'输入错误: 颜色必须是三元素向量.')
assert(numel(x)==numel(y),'输入错误:：x 和 y 维度必须相等')
assert(isscalar(sigma)==1,'输入错误: sigma必须是标量.')

%% Input parsing

tmp = strncmpi(varargin,'resolution',3);
if any(tmp)
    res = varargin{
    find(tmp)+1};
    if isscalar(res)
        res = [res res];
    else
        assert(numel(res)==2,'输入错误: 分辨率必须是标量或二元素向量.')
    end
else
    res = 2500*[1 1];
end
tmp = strncmpi(varargin,'average',2);
if any(tmp)
    avg = varargin{
    find(tmp)+1};
    assert(isscalar(avg)==1,'输入错误: 移动平均距离必须为标量.')
    y = imfilter(y(:),fspecial('average',[avg 1]),'replicate');
end
buffer = 3*sigma; % This is the padding to add around all measurements in the vertical dimension.
%% 限制范围:
% 制作一个与数据缓冲区的尺寸相对应的网格:
[X,Y] = meshgrid(linspace(min(x),max(x),res(1)),linspace(min(y)-buffer,max(y)+buffer,res(2)));
% Find y locations along all x points of the grid
yi = interp1(x,y,linspace(min(x),max(x),res(1)));
% 正态分布:
P = (1/sqrt(2*pi*sigma^2)) * exp(-(bsxfun(@minus,Y,yi)).^2/(2*sigma^2));
%每个点到yi的距离将用作透明度的量度:
Z = P-min(P(:));
Z = Z/max(Z(:));
%创建指定颜色的RGB图像:
RGB = cat(3,color(1)*ones(size(Z)),color(2)*ones(size(Z)),color(3)*ones(size(Z)));
% 绘制颜色的RGB图像:
h = image(RGB,'xdata',X(1,:),'ydata',Y(:,1));
axis xy
% 设置透明度:
set(h,'alphadata',Z)
% 将渲染器设置为OpenGL，因为透明度仅适用于OpenGL:
set(gcf,'renderer','OpenGL');
% 底部:
uistack(h,'bottom')
%% 清除:
if nargout==0
    clear h
end
end