How to rename all the variables?

[Guest]

Hi,

I want to rename all the variables by adding _year to all of them at the end (eg. religion_2005). However, I cannot understand if there is a command which will allow this. Just like there is a command for adding a prefix.

I have more than 1,000 variables and renaming for each variable can be a very tedious task.

[Clyde Schechter]

Do you actually want to add _2005 to every variable in the data set? What's the point of that? If they're all 2005, there's nothing gained by noting that. I'm going to assume that some of your variables you want to rename _, and another group you want to name _2006, etc.

Now, at some point, you have to designate which variables get which suffix. (And probably there are some that get no suffix at all.) There will be no choice but to list those out, or use wildcards to identify them. Anyway, you will need to create local macros containing these lists. So something like

local 2005_vars var_a var_b var_c // etc.
local 2006_vars var_x var_y var_z // etc.

forvalues y = 2005/2006 {
   rename (`y'_vars) =_`y'
}

More generally, read -help rename group- to see the large number of commands that Stata provides for all sorts of bulk renaming of variables.

[Zhe Zhang]

Agree with Clyde. Under most circumstances, it is unnecessary to add _year to every variable. But if it's really what you want, try this simple code:

rename * *_2005

[Charlene Rapsey]

I've read this thread as I would like to add a suffix to all variable names - the reason is that I want to merge two datasets for longitudinal analysis - so I have 2021 data and 2022 data, which share common variable names - to be able to add the 2022 variables to the 2021 data and then work with the data wide or long, I think that the best way is to rename all of the variables with e.g. _1 and _2 (unless there is a better way to achieve this goal). Using the code above, I get the following error:

. rename * *_2
1 new variable name invalid
    You attempted to rename Create_a_New_Field_or_Choose_fro to
    Create_a_New_Field_or_Choose_fro_2.  That is an invalid Stata variable name.
r(198);

[Clyde Schechter]

It's an invalid name because "Create_a_New_Field_or_Choose_fro_2" is 34 characters long, and the maximum permissible length of a variable name is 32 characters. So if you want to add suffixes _1 and _2, you will have to take any variable name that is longer than 30 characters and reduce it to 30 characters (usually by dropping the last two, but be careful you don't end up trying to give two different variables the same name). Then you can use the -rename * *_2- command.

Another possibility is this: if all of the variables in the two data sets have the same names, then you probably should combine them with -append- rather than -merge-. And in that case you should not rename the variables. You should just add a year variable to the data sets before appending them. Or, perhaps simpler, use -append-'s -generate()- option to create a variable distinguishing the two file sources.

[Charlene Rapsey]

Brilliant - thanks so much - great to understand the error - and, I think you're right, append is probably the better option.