matlab - 如何在分组栏中绘制误差线？

Question

我想在分组条中绘制误差条。我写了下面的代码

x = categorical({'a', 'b', 'c', 'd', 'e'});
y = [6816,7215; 5824,6180; 4860,5200; 3860,4206; 2838,3185];
errlow = [238,337;270,355;303,297;291,340;259,382];
errhigh = [231,264;225,337;153,171;185,286;167,247];

b = bar(x,y);

hold on

xtips1 = b(1).XEndPoints;
ytips1 = b(1).YEndPoints;

er = errorbar(xtips1, ytips1, errlow(:,1), errhigh(:,1));    
er.Color = [0 0 0];                            
er.LineStyle = 'none';

hold on

xtips2 = b(2).XEndPoints;
ytips2 = b(2).YEndPoints;

er2 = errorbar(xtips2, ytips2, errlow(:,2), errhigh(:,2));    
er2.Color = [0 0 0];                            
er2.LineStyle = 'none';

hold off

ylim([2400 7600]);

错误栏显示在图表中。请看一下，它们直接位于 a、b、c、d 和 e 上方，但不在条形图上，如图所示。

我希望它们位于关联的栏上(“绿色”标记的错误应位于右侧栏，而“红色”标记的错误应位于左侧栏)，如图所示。我该怎么做？

提前致谢!

Answer 1

这是 MathWorks Support Team 提供的答案，如发布于MATLAB Answers (一些小的修改除外)。

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The ability to specify that the errorbar function should display the error bars inside the patches is not available in MATLAB. There are two work arounds for this limitation, usage of which depends on the release of MATLAB that you are using.

1. If you are using R2019a or earlier releases, find the center of each bar and pass this data into errorbar with the respective error values.
2. If you are using R2019b or later releases, retrieve the x coordinate of each bar using the XEndPoints property and pass this data into errorbar.

The following is an example of the above:

% Example data
model_series = [10 40 50 60; 20 50 60 70; 30 60 80 90];
model_error = [1 4 8 6; 2 5 9 12; 3 6 10 13];
b = bar(model_series, 'grouped');

对于 MATLAB R2019a 或更早版本:

hold on
% Find the number of groups and the number of bars in each group
ngroups = size(model_series, 1);
nbars = size(model_series, 2);
% Calculate the width for each bar group
groupwidth = min(0.8, nbars/(nbars + 1.5));
% Set the position of each error bar in the centre of the main bar
% Based on barweb.m by Bolu Ajiboye from MATLAB File Exchange
for i = 1:nbars
    % Calculate center of each bar
    x = (1:ngroups) - groupwidth/2 + (2*i-1) * groupwidth / (2*nbars);
    errorbar(x, model_series(:,i), model_error(:,i), 'k', 'linestyle', 'none');
end
hold off

对于 MATLAB 2019b 或更高版本:

hold on
% Calculate the number of bars in each group
nbars = size(model_series, 2);
% Get the x coordinate of the bars
x = [];
for i = 1:nbars
    x = [x ; b(i).XEndPoints];
end
% Plot the errorbars
errorbar(x',model_series,model_error,'k','linestyle','none')'
hold off