st: RE: RE: RE: destringing and replacing values for several variables

["Nick Cox" <n.j.cox@durham.ac.uk>]

-destring- is a marvellous command, but I agree with Martin that
-encode- is the way to go here. 

By the way, -multencode- from SSC lets you multiply encode based on the
same value labels. 

Nick 
n.j.cox@durham.ac.uk 

Martin Weiss

Glad it worked out for you! Re loops, you may want to try NJC`s
http://www.stata-journal.com/sjpdf.html?articlenum=pr0005

Ann Miller

Thank you very much for this reply. This one in particular worked
beautifully and -encode- saved me several steps. 

"Martin Weiss" <martin.weiss1@gmx.de> 4/21/2010 3:51 PM >>>

Ann, you could -encode- one of those "hf_stage*" fellows outside of your
loops, and then apply the same -label- to everybody else inside a loop:

encode hf_stage1, gen(hf_stage1numeric) label(myhflabel)

foreach var of varlist hf_stage2-hf_stage40{
	encode `var', gen(`var'1numeric) label(myhflabel)
}

la list myhflabel
ta  hf_stage1numeric
ta  hf_stage1numeric, nolabel

If anybody wants to put himself/herself in Ann`s shoes, this is what her
data look like in my view:

*******
clear*
set obs 100

foreach var of newlist hf_stage1-hf_stage40{
	gen str10 `var'="Stage 1" 
	replace `var'="Stage 2" in 1/30	
	replace `var'="Stage 3" in 39/40	
	replace `var'="Stage 4" in 46/80	
}
*******

Ann Miller

I am new to macros and the foreach looping and am trying to simplify my
life. I have a list of 40 or so variables (ex: hf_stage1 through
hf_stage40)
that all have the same string coded values; "Stage 1" "Stage 2" "Stage
3"
"Stage 4". I want to change these values to 1, 2, 3 and 4, with value
labels
of "Stage 1" "Stage 2" "Stage 3" and "Stage 4". What I have done in the
past
is: 

 replace hf_stage1="1" if hf_stage1=="Stage 1"
 replace hf_stage1="2" if hf_stage1=="Stage 2", etc., 
destring hf_stage1,replace
 and for each value generate a label.

 I then have to repeat this for every variable (hf_stage2 through
hf_stage40). It works, but is time consuming and I sometimes make
mistakes.
I feel sure there's a way to do this with macros and foreach but there's
something I'm missing so far. 

Here's what I've tried:

local varlistfoo "hf_stage1 hf_stage2 hf_stage3"



. foreach var of `varlistfoo' {
  2. replace  var= "1" if  var=="Stage 1"
  3. replace  var= "2" if  var=="Stage 2"
  4. replace  var= "3" if  var=="Stage 3"
  5. }
invalid syntax
r(198);

. foreach varname of varlist  hf_stage1 hf_stage2 hf_stage3{
  2. replace  varname= "1" if  varname=="Stage 1"
  3. replace  varname= "2" if  varname=="Stage 2"
  4. }
variable varname not found
r(111);


I can't even get the first step, let alone destringing and replacing!
Any
advice you all can offer would be greatly appreciated.Thank you!

*
*   For searches and help try:
*   http://www.stata.com/help.cgi?search
*   http://www.stata.com/support/statalist/faq
*   http://www.ats.ucla.edu/stat/stata/