horizontal error bars in Matlab

I've had a number of questions about horizontal error bars on Matlab plots. To this point you have probably been able to get away without having them because your errors in the abscissa have been negligible...not so on Lab 5 however, as you will find there is a decent amount of uncertainty in the entropy on your T-S diagrams.

Unfortunately, the Matlab plotting library has a number of deficiencies (in my opinion, anyways), one of which is omissions of a function to create x-axis error bars automatically like you can do with the function call errorbar. In order to plot these, you will have one of three options:

1) Use another utility to do your plots (not Excel!)
2) Find a script online that someone else has written to do horizontal error bars in Matlab
3) Write your own script to perform this function

If you choose option 3, the good news is that this code can be very simply implemented in about 5 lines (I know because I went back to my office after lecture and sat down and wrote it out). I'm not going to post this on CTools because I do want to make sure everyone is trying to do this work for themselves...

...however, if you find yourselves stuck after working on it this weekend, I will help you out with this code in office hours on Monday and Tuesday (so I will make sure that everyone has this capability). I'm only hesitant to just post it up to CTools so the people that may have already done the work feel cheated that I just gave it away to everyone else. Rest assured though, if you can't get it working, I'll help you out with the particulars of the Matlab code.

Regarding option 1, you say not to use Excel but don't offer an explanation why. Is there a particular reason why you don't want us using Excel? I know how to easily fulfill all of the requirements for this lab's plots using Excel, including the addition of vertical and horizontal error bars and manipulation of formatting to make it all look good.

The explanation (or, at least the best one I can give) is that TechCom and the professors have explicitly mentioned throughout the semester that Excel plots are not acceptable for the lab reports. That's not my rule...it's the rule for the class we all have to deal with.