Plotting error bars?

I would like to plot error bars representing the standard deviation of x values, but at the moment the error bars on my graph are only appearing in the vertical axis? Is there anyway I can change the orientation so they are in the correct axis?

Here's the script i'm working with:

x = [12.755  9.1827 6.9252 5.4083  4.3403];
y = [408 265 236 139 124];

coeffs = polyfit(x , y, 1);
yfit = polyval(coeffs, x);
res = y - yfit ;
xfit = x;

SE = std(x)/sqrt(5);
SD = std(x)
err = [SD SD SD SD SD]

grad = (yfit(1) - yfit(5)) / (x(1) - x(5));

disp(['The gradient of the trendline = ', num2str(grad)])

errorbar(x, y, err, 'blue')

hold on

plot(x ,y, 'x', xfit, yfit, 'r-+', 'LineWidth',1.1)

set (gca, 'FontName', 'Century')

grid on

grid minor

title('Plot of buckling load vs 1/Length for fixed-fixed end condition')

ylabel('Pcr / N');

xlabel('1/L^2 / m^2')

legend('Standard Deviation', 'Data Points', 'Trendline')

Answer 1

[the cyclist]

The documentation for errorbar describes how to add both horizontal and vertical error bars.

(Unless you have an older version of MATLAB, which I think might not have had horizontal bars.)

[Tre Davidson]

no it does not

[the cyclist]

This link will take you directly to the documentation example of plotting both horizontal error bars. Here is the code:

x = 1:10:100;
y = [20 30 45 40 60 65 80 75 95 90];
err = [1 3 5 3 5 3 6 4 3 3];
errorbar(x,y,err,'horizontal')

So, I'm not sure why you claim it doesn't.