st: RE: renaming variables

["Seed, Paul" <paul.seed@kcl.ac.uk>]

I'm afraid there is a problem with Nick Cox's elegant solutions 
to Abhimanyu Arora's problem.

Abhimanyu asked:
"I would like to rename my variables var53....var108 such that var53,
var56, var59 ......var107 etc...are renamed as year1990,
year1991......year2008 repectively. I tried to use renvars(by Jeroen
Weesie) and a forvalues loop, but am not able to succeed.

And Nick suggested 


//-rename-
loc start 1990

foreach var of varlist var* {
	ren `var' year`start'
	loc ++start
}

However, the use of var* assumes a very unusual data set, in
which the only "varX" variables are the year variables 
that need renaming, and they are spaced 3-apart with nothing 
in the gaps. This is the case in the artificial example Nick produces:

clear
set obs 1
forv i=53(1)107{
	gen var`i'=1
}


Consider perhaps a more realistic data set:
clear
sysuse auto
forv i=40(1)107{
	gen var`i'=1
}

Now Nick's solution needs to be adapted slightly.


//-rename2-

loc start 1990
forv i=53(3)107{
	ren `var'`i' year`start'
	loc ++start
}

It can also be extended to other variables.
I assume that year is in each case the first 
(rather than the second or last) of a
cluster of 3 variables: 

//-rename3-

loc start 1990
forv i=53(3)107{
	ren `var'`i' year`start'
	local j = `i' + 1
	ren `var'`j' thing_one_`start'
 	local j = `i' + 2
	ren `var'`j' thing_two_`start'
	loc ++start
}


(with acknowledgements to Dr Seuss)
http://en.wikipedia.org/wiki/The_Cat_in_the_Hat

*********************************************************************
Paul T Seed 
King's College London, Division of Reproduction and Endocrinology  
St Thomas' Hospital, Westminster Bridge Road, London SE1 7EH
*********************************************************************



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