Rename To Reshape

[Leon Edelman]

Hi All,

Suppose you have repeated variables at different assessments: A1SMOKE A2SMOKE A3SMOKE A4SMOKE. And you want to reshape these into long format. How can I loop it to rename them SMOKE1 SMOKE2 SMOKE3 SMOKE4 or SMOKEA1 SMOKEA2 SMOKEA3 SMOKEA4. I have to do this for many variables but have not seen a loop that will assist. Cheers.

[Jorrit Gosens]

rename *SMOKE SMOKE*

Or if you mean to say you have more such repeated variable names components:

local stubnames "SMOKE XYZ"
foreach stub of local stubnames{
ren *`stub' `stub'*
}

[Daniel Bela]

Hi Leon,

without a proper data example (see the FAQ, especially section 12.2, on how to create such), this is only guesswork, but I don't think you have to rename your variables at all. reshape's syntax features a mechanism to directly specify where in the variable (stub-)names it should search for the enumerator:

clear
input id A1SMOKE A2SMOKE A3SMOKE A4SMOKE
1 1 1 1 1
2 2 2 2 2
3 3 3 3 3
end
reshape long A@SMOKE , i(id) j(wave)

See help reshape.

Kind regards
Bela

[Nick Cox]

Jorrit and Daniel both give excellent advice. But I'll add that on the whole, and in my experience, making prefixes informative is the better way to go. So, I'd prefer names smoke* to names *smoke.

[Festus odingo]

I hope this helps, it will not rename your variables but once they are well renamed then you can incorporate the prefix of your variables in foreach line and the resultant variable in the reshape line; you should have something that looks like this:
local stubnames "SMOKE XYZ" foreach stub of local stubnames{ ren *`stub' `stub'* } ***then...

foreach v in smoke* climate* truck*{
local l`v' : variable label `v'
}
macro list

reshape long smoke climate truck, i(id) j(time)

foreach v of var * {
local L`v' : variable label `v'
if `"`L`v''"' == "" & `"`l`v''"' != "" {
label var `v' `"`l`v''"'
}
}

[Nick Cox]

This won't work. Look at

foreach v in smoke* climate* truck*{
local l`v' : variable label `v'
}

That is going to fail first time round the loop when you try

local l`v' : variable label smoke*

as you're feeding a wildcard where a variable name is expected.

[Leon Edelman]

Is it possible to reshape long when your data look like

A5SMOKE	A1SMOKE	A2SMOKE	A3SMOKE	A4SMOKE
0	1	1	0	1
1	1	1	0	0

[Nick Cox]

#7 looks like the same question as already answered. If the difference is the order of variables, that's immaterial.

#3 already gave advice on better ways to present data. We really want you to take it.