Re: st: Setting a missing value in a generic context

[David Kantor <dkantor@jhu.edu>]

Thanks to Morten for that suggestion.

It is useful, in that it takes the required code and packages it into a 
program (and can eliminate repeated coding), but I was hoping that there 
might be something built-in that does it.  On the other hand, any solution, 
whether programmed or built-in, would need to do such a test of the type 
anyway. So a built-in, if it existed, might not be much better.

If you are interested, I have used similar code in a slightly different 
way, which enables either -replace- or -post- (or both):

local typ: type `v'
if substr("`typ'", 1, 3) == "str" {
 local missvalue = `""""'
}
else {
 local missvalue = "."
}

...
replace `v' = `missvalue'

or:

postfile postname `typ' var1 ...
...
post postname  (`missvalue') ...

Thanks,
-- David

At 06:32 PM 3/5/2005 +0100, you wrote:

> Hi David,
>
> You actually provided the solution yourself. Just wrap it up into
> repmiss.ado:
>
> program repmiss
>     version 8
>     syntax varname [if] [in]
>     local typ: type `varlist'
>     if substr("`typ'", 1, 3) == "str" {
>       replace `varlist' = "" `if' `in'
>     }
>     else {
>       replace `varlist' = . `if' `in'
>     }
> end
>
> However, when using post you can't get around knowing the variable types, I
> believe.
>
> Regards,
>
> Morten
>
> ----------------------------------------------------------------------------
> Morten Andersen, MD, PhD               Research Unit for General Practice
> Senior Researcher                      University of Southern Denmark
> Phone   +45 6550 3791                  J.B. Winsloews Vej 9
> Fax     +45 6311 1642                  DK-5000 Odense C
> E-mail  mandersen@health.sdu.dk        Denmark
> ----------------------------------------------------------------------------
>
> Hi everyone,
>
> Is there a concise way to set a variable to a missing value if you don't
> know its type (string vs. numeric)?  This would be the reverse of the mi()
> function -- reverse in that you are setting rather than testing the value.
>
> Suppose I have a local v that contains a variable name, and I want to
> replace the variable to missing.
> [...]
>
> What I'd like is something like
>   replace `v' = universal_missing_symbol_that_works_regardless_of_data_type
> [...]
David Kantor
Institute for Policy Studies
Johns Hopkins University
dkantor@jhu.edu
410-516-5404
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