Error Bars on horizontal bar chart

Hi.

I am trying to produce a horizontal bar chart with error bard, but the error bars minimum value seem completely wrong. Also, the positions of the vertical 'ends' of each error bar appear to be in the wrong position. What am I doing wrong?

Here is the code that produced this chart below:

% data
min =  [1e-4 1e-3 1e-2 1e-1 1e1];
mean = [1e-3 1e-2 1e-1 1e1  1e2];
max =  [1e-2 1e-1 1e1  1e2  1e3];
cats = categorical({'a','b','c','d','e'});
% plot horizontal bars
figure; hold on;
p = barh(cats,mean,...
    'FaceColor',[0.75,0.75,0.75],...
    'EdgeColor','k',...
    'LineWidth',1.5,...
    'BaseValue',1);
baseline = p.BaseLine;
% change xscale to 'log'
ax = gca;
ax.XScale = 'log';
baseline.LineWidth = 1.5;
% add y tick labels
ax.YTickLabel = {'cat a','cat b','cat c','cat d','cat e'};
% plot error bars
er = errorbar(mean,cats,min,max,'.','horizontal');
er.LineWidth = 1.5;
er.Color = 'k';
er.MarkerSize = 1;

[Adam Danz]

The error bars are being draw accurately according to your data. The left and right columns below are the distance of the lower or upper error bar from the value in the middle column. Your 'mean' values are nowhere near centered in those ranges.

>> [min', mean', max']
ans =
       0.0001        0.001         0.01
        0.001         0.01          0.1
         0.01          0.1           10
          0.1           10          100
           10          100         1000

From doc errorbar: errorbar(x,y,neg,pos) draws a vertical error bar at each data point, where neg determines the length below the data point and pos determines the length above the data point, respectively.

[Glaucia Fragoso]

I don't know how you did this... when I try I get an error "X-data must be the same size as Y-data"

[Adam Danz]

The error message tells you what's wrong. Your x-data must be the same size as your y-data.

x = 1:5; 
y = 1:6; 
e = 1:6; 

errorbar(x,y,e)

Error using errorbar
X-data must be the same size as Y-data.

Answer 1

[dpb]

"errorbar(x,y,neg,pos) draws a vertical error bar at each data point, where neg determines the length below the data point and posdetermines the length above the data point, respectively."

Looks like it did exactly what you askied it to do...it added the min,max values to the mean value and drew the errorbars at those computed limits. It appears instead you intended

er = errorbar(mean,cats,mean-min,mean+max,'.','horizontal');

BTW, do NOT use mean, max, min as variable names; they are the builtin functions of the same meaning; aliasing them will undoubtedly wreak havoc later on when you expect them to function normally. Use some identifier to differentiate like xmean, xmax, xmin or the like instead.

[Adam Danz]

+1 for warning about variable names.

[Nshine]

thanks dpb!