Michael,
Thanks for the quick reply but lineno==mlineno is never true because
one cannot be one's own mother.
Friedrich
--- Michael Blasnik <[email protected]> wrote:
> assuming 1 mother per household, how about no loop at all:
>
> egen mage=max(age*(lineno==mlineno)), by(hhid)
>
> This would result in a 0 for any household without a mother listed,
> which
> you could easily change to missing or whatever you like.
>
> Michael Blasnik
> [email protected]
>
> ----- Original Message -----
> From: "Friedrich Huebler" <[email protected]>
> To: <[email protected]>
> Sent: Wednesday, September 15, 2004 11:33 AM
> Subject: st: How to speed up loop
>
>
> > I am looking for advice to speed up a loop. The loop determines
> > characteristics of other household members in household survey
> data
> > and is taken from this Stata FAQ:
> >
> > http://www.stata.com/support/faqs/data/members.html
> >
> > The data has the variables hhid (household ID), lineno (line
> number
> > of household member), age, and mlineno (mother's line number).
> >
> > hhid lineno age mlineno
> > 1 1 32 .
> > 1 2 30 .
> > 1 3 5 2
> > 2 1 68 .
> > 2 2 41 1
> > 2 3 40 .
> > 2 4 17 3
> > 2 5 14 3
> >
> > The following code creates the variable mage with the mother's
> age.
> >
> > gen byte mage=.
> > sum lineno, meanonly
> > forvalues i = 1/`r(max)' {
> > gen byte tag = 1 if lineno==`i'
> > bysort hhid: egen byte iage = max(tag*age)
> > replace mage=iage if mlineno==`i'
> > drop tag iage
> > }
> >
> > I tried changing -bysort hhid- to -by hhid- but the time needed
> for
> > the loop is the same. Running the loop -quietly- also makes no
> > difference. Can anything be done to make this loop go faster?
> >
> > Thank you,
> >
> > Friedrich Huebler
_______________________________
Do you Yahoo!?
Declare Yourself - Register online to vote today!
http://vote.yahoo.com
*
* For searches and help try:
* http://www.stata.com/support/faqs/res/findit.html
* http://www.stata.com/support/statalist/faq
* http://www.ats.ucla.edu/stat/stata/
