Re: st: RE: looping up to a local macro

[Nick Cox <njcoxstata@gmail.com>]

Michael has not (yet) clarified the situation with his varlists, so
that we cannot decide between

optimistic take: his -letter0*- could be just -letter01- up with the *
standing for successive integers to some maximum

pessimistic take: his -letter0*- could be a mix of variables as above
and other irrelevant variables also starting with -letter0-.

Here's a method to segregate the two, on the latter take.

unab all : letter0*
local suffixes : subinstr local all "letter0" "", all
local count : word count `suffixes'
numlist 1/`count'
local integers `r(numlist)'
local suffixes : list integers & suffixes

Now, even on the pessimistic take, Michael could loop

foreach s of local suffixes {
      rename letter0`s'  letter`s'
      ...
}

Here is another way to get that list of suffixes

unab all : letter0*
local suffixes : subinstr local all "letter0" "", all
local OK

foreach s of local suffixes {
       capture confirm number `s'



On Thu, Jun 23, 2011 at 12:16 AM, Nick Cox <njcoxstata@gmail.com> wrote:
> It's true that there could be other variables such as
> -letter0aardvark-, -letter0bison-, -letter0coypu-, and so forth.
>
> On Thu, Jun 23, 2011 at 12:13 AM, Nick Cox <njcoxstata@gmail.com> wrote:
>> I don't think it's clear that any explicit looping or macro
>> manipulation is needed at all. Michael wants to change a bunch of
>> variables -letter01- on to -letter1- on , for which a solution is
>>
>> renpfix letter0 letter
>>
>> -renpfix- has long been an official command.
>>
>> The -recode- part will take a varlist, so looping is also unnecessary for that.
>>
>> However, I can't vouch for what is needed to speed up the unspecified
>> lines of code.
>>
>> Nick
>>
>> On Wed, Jun 22, 2011 at 11:20 PM, Sarah Edgington <sedging@ucla.edu> wrote:
>>> Michael,
>>> What do you mean by "I can't quite get it to work"?  What problem are you
>>> having?
>>> Without more information about what's going wrong it is really difficult to
>>> offer much assistance.  The form of your loop looks fine.  Maybe there's
>>> some problem with the code in the loop itself.  Does it work if you specify
>>> a number instead of the local macro?  You're setting the value of letters in
>>> the same dofile as the forvalues loop, right?  If you aren't that's going to
>>> be a problem.
>>
>>  Michael Costello
>>
>>> I'm writing to ask about combining loops with local values.  I have a local
>>> macro that I need to set equal to some value, different for each database.
>>>  Let's say, for example, 50 in one db, 100 in another.  Then I want to
>>> preform some loop operation on all the variables from
>>> letter1 up to letter50 or letter100 (depending on the database).  Is that
>>> possible, with some change to the code below?  I can't quite get it to work.
>>>
>>> local letters 100
>>>
>>> forvalues i = 1(1)`letters' {
>>>   quietly: rename letter0`i' letter`i'
>>>   quietly: recode letter`i' (9=.) (2=1) (1=0)
>>>   * more lines of code here
>>> }
>>>
>>> Basically, instead of copy ~400 lines of code into several dozen cleaning
>>> files, I'd like to just set  the maximum value (50, 100, 20,
>>> etc) for the database and have it run one cleaning file.  Thanks for any
>>> help you can provide!
>>
>

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