Renaming part of a variable using loops

[Wyatt Pracht]

I am trying to rename a large number of variables that correspond to various survey waves. We have to follow up surveys where each variable from the first follow up end begins with "a_" and each variable name from the second follow-up begins with "b_".

I would like to rename each of these variables using a loop but want to switch the "a_" and "b_" from the beginning of the each of the variable names to the end so each variable shows up as "var_a" and "var_b"

I have the following code to add the "_a" and "_b" to the end of the variables but am unsure how to rename the variables to drop "a_" and "b_" from the front part of the variable names.

My current code is:
global a_varlist vars
foreach var of varlist $a_varlist {
rename `var' `var'_a
}

global b_varlist vars
foreach var of varlist $b_varlist {
rename `var' `var'_b
}

[Chen Samulsion]

It's unnecessary to use a loop, but what is the real variable names in your dataset? Just a_, b_, ......? Suppose your variables are named a_here, b_there, then

rename (a_*) (*_a)
rename (b_*) (*_b)