You forgot to add hold on before calling errorbar so that wiped out the barplot and then each subsequent call to it also will have overwritten the previous. But, that alone won't solve your problem because with a grouped bar, the locations aren't in the center of the bars but at the center of each group. I've complained for 20+ years and TMW has yet to do anything really positive to solve the horrendous interface to bar and to provide easy ways to do the obviously-needed such as this; I would strongly suggest to add your voice to the complaints about quality of implementation being lacking and the need for the facility to be included as a standard set of options in one manner or another. OK, editorializing over, see
<Answers:379570-how-can-i-place-my-error-bar-in-separate-bar-center> for example of how to locate the positions and to do what you're asking for.
