Using errorbar in MATLAB with asymmetric errorbars

Having difficulty using the matlab function errorbar. I'm trying to put errorbars on a plot I drew.

I have a line, y = theta, and a vector of errors named momeerr95.

I tried using errorbar with

errorbar(y, momeerr95, 'rx')

and was returned an error that said "X, Y, and error bars all must be the same length."

Can anyone explain my error or how I might go about plotting these error bars?

[the cyclist]

What are the outputs of

size(y)

and

size(momeerr95)

?

The error you are getting suggests that they are of different size.

Answer 1

[pfb]

My guess is that momeerr95 contains both the upper and the lower values for the errorbars. Or else, how would matlab know that the errorbars are not symmetric? Assuming y is a row vector, I guess that momeerr95 has the same number of columns as y, and two rows instead of one.

Anyway, the answer is in the first sentence of the help for the command "errorbar", which you can summon by typing "help errorbar".

 errorbar(X,Y,L,U) plots the graph of vector X vs. vector Y with error bars specified by the vectors L and U...

Apparently you do not have abscissae, so you can define x=1:length(y). Then you have to create two vectors L and U for the lengths of the semi-errorbars. Of course all of the vectors must have the same size.