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It might help if you submit a toy dataset to describe how your data look.
For example
Patient   var1      var2      var3      
1001      1234      V234      med       
1002      1233      1431      small     
1003        65      14-1      small     
1004       2.4       333      large     

In this case, Stata would bring "Patient" in as a numeric variable, var2 and
var3 as string variables, and var1 as numeric.

Now, had the data looked like
Patient   var1      var2      var3      
1001      1234      1234      med       
1002      1233      V234      small     
1003        65      14-1      small     
1004       2.4       333      large     
     
Stata would have decided that var2 should come in as a numeric variable, and
you would end up with

patient   var1      var2      var3      
1001      1234      1234      med       
1002      1233         .      small     
1003        65         .      small     
1004       2.4       333      large     

(notice also that Stata will change Patient to patient, although it will
store "Patient" as a variable label)

Likewise, if you took the first example and process it with
.destring, replace force 
(which is pretty reckless, data integrity-wise), you'll end up with

patient   var1      var2      var3      
1001      1234         .          .      
1002      1233      1431          .     
1003        65         .          .     
1004       2.4       333          .     

Is this along the lines of your situation?

-JW

-----Original Message-----
From: Suzy [mailto:scott_788@wowway.com] 
Sent: Friday, August 27, 2004 4:06 PM
To: statalist@hsphsun2.harvard.edu
Subject: Re: st: RE: destringing values led to Stata recoding them as
missing

I meant to say -  would the restring option restore my datapoints?

Suzy wrote:

> Hi John,
>
> I don't know if this matters but I'm not starting with purely string 
> variables. I have variables that have datapoints of which some are 
> string and some are numeric. Also John, would the destring option 
> restore my original values as now the destringed values are missing....
> Suzy
>
> Wallace, John wrote:
>
>> Suzy
>> You might want to consider -encode- instead of destring.  Presumably 
>> you're
>> starting with string variables.  Encode will create a new variable with
>> incrementing value in (I believe) alphabetical order of the original
>> variable, plus it will make a value label corresponding to the original
>> string.  This is useful if you need to be able to relate the new 
>> variable
>> value back to the original string.
>>
>> e.g.
>> .encode var1, gen(code1)
>>
>> -JW
>>
>> -----Original Message-----
>> From: Suzy [mailto:scott_788@wowway.com] Sent: Friday, August 27, 
>> 2004 2:45 PM
>> To: statalist@hsphsun2.harvard.edu
>> Subject: st: destringing values led to Stata recoding them as missing
>>
>> Dear Statalisters;
>>
>> I have seven variables of over 300,000 observations each. Within 
>> each  variable, I have over 2000 different  values.  These datapoints 
>> represent  specific codes - for example : (72200  = intervertebral 
>> disc disorder). Within each of these  seven variables, there are 
>> datapoints (values) with dashes or alphabets (Ie: 4109-  or V2389).  
>> The majority of the values though, are purely numeric (23405). I used 
>> the destring option so that I could analyze the data and Stata 
>> treated all those datapoints that included dashes and alphabets as 
>> missing. Now there is a period . where there used to be a value.  I 
>> have two questions:
>>
>> 1. Will the restring option restore the datapoints?
>>
>> 2. How can I successfully "destring" these values so that I can 
>> include them in my analysis?
>>
>> Any  help and/or specific code would be very helpful as I am only 
>> marginally competent with Stata basics.
>>
>> Thank you!
>> Suzy
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