Graph bar for categorical variable, but sorted in prespecified order

[Jonathan Horowitz]

This is a stunningly simple problem and I know there is a stunningly simple answer, but I can't figure it out.

I want to graph a categorical variable, such as a grade distribution of letter grades. I can do this pretty easily with:

graph bar, over(grade)

The problem with this is that it's out of order, with A coming before A+, B coming before B+. In addition, I would prefer to reverse it so that "F" is at the bottom.

Based on the help file, I think the right solution is to create a new variable and then sort by it. So I did this:

gen ordvar=1 if Grade=="F"
replace ordvar=2 if Grade=="D-"
replace ordvar=3 if Grade=="D"
replace ordvar=4 if Grade=="D+"
replace ordvar=5 if Grade=="C-"
replace ordvar=6 if Grade=="C"
replace ordvar=7 if Grade=="C+"
replace ordvar=8 if Grade=="B-"
replace ordvar=9 if Grade=="B"
replace ordvar=10 if Grade=="B+"
replace ordvar=11 if Grade=="A-"
replace ordvar=12 if Grade=="A"
replace ordvar=13 if Grade=="A+"

graph bar, over(Grade, sort(ordvar))

The result is that I get this error message:

variable mean not found

Is there an alternative way to do this that I am missing? I am convinced that there is a simple solution that I can't think of.

[Jonathan Horowitz]

Update: Immediately after I posted this, I accidentally stumbled across this article by Nick Cox: https://core.ac.uk/display/6990279

And this more or less solves the problem.

generate freq=1
graph bar (percent) freq,  over(Grade, sort(ordvar))

That said, I still don't really understand why the other version didn't work.

[Nick Cox]

Good question. I would send this in to StataCorp technical support.