Replace $ in Stata variable labels with \textdollar

Question

I have some variables with dollar signs (i.e., $) in the variable labels. This causes some problems downstream in my code (I later modify these labels and the dollar signs deregister as empty global macros). So I would like to replace these dollar signs with LaTeX's \textdollar using Stata's subinstr() function.

But I can't figure it out. Is this possible? Or should I resign to doing this more manually? Or by looking for other characters near or around the $ in the variable labels?

clear
set obs 10
generate x = runiform()
label variable x "Label with $mil"
generate y = runiform()
label variable y "Another label with $mil"

describe
foreach v of varlist * {
    local name : variable label `v'
    local name `=subinstr("`name'", "$mil", "\textdollar", .)'
    label variable `v' "`name'"
}
describe

This removes the label altogether.

Roberto Ferrer Roberto Ferrer · Accepted Answer · 2014-12-16T20:05:03

(The problem has completely changed, which is why I give a separate answer.)

Having $something in the variable label is somewhat problematic because Stata will treat it as a macro and will therefore dereference it. What is actually Stata doing in your toy example? Let's see:

This is expected behavior:

. local name = subinstr("some text", " ", "xyz", .)

. display "`name'"
somexyztext

The following, which I don't know if documented, is not necessarily expected but crucial in understanding:

. local name = subinstr("some text", "", "xyz", .)

. display "`name'"

. (blank)

I put in the last line to emphasize that the local name has nothing.

In your code Stata dereferences $mil to nothing (because it's not declared beforehand; it's not meant to, of course). In fact,

label variable x "Label with $mil"

does not hold what you intend. Rather you want to delay macro substitution with \:

label variable x "Label with \$mil"

For the other part, when you run this

local name `=subinstr("`name'", "$mil", "\textdollar", .)'

it evaluates to

local name `=subinstr("`name'", "", "\textdollar", .)'

and the local name now holds nothing. That ends the story of why your code does what it does.

A solution might be:

clear

set obs 10

generate x = runiform()
label variable x "Label with \$mil"

generate y = runiform()
label variable y "Another \$mil"

describe

*-----

foreach v of varlist _all {

    local name : variable label `v'
    label variable `v' "`=subinstr("`name'\$mil", "\$mil", "\textdollar", .)'"
}

describe

but this only works if $mil is at the end of the label text. If it is in the middle somewhere, another strategy must be used.

All this on Stata 12.1.

Replace $ in Stata variable labels with \textdollar

2 Answers