st: RE: Copying the contents of existing variables into a new variable

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

The -generate- command you give is fine. 

. clear 

. input var1  var2   

          var1       var2
  1. 345    .       
  2. 345    .       
  3. 345    .       
  4. 345    .       
  5. .       678    
  6. .       678    
  7. .       678    
  8. .       678    
  9. end 

. gen newvar = max(var1, var2) if missing(var1, var2) 

. l 

     +----------------------+
     | var1   var2   newvar |
     |----------------------|
  1. |  345      .      345 |
  2. |  345      .      345 |
  3. |  345      .      345 |
  4. |  345      .      345 |
  5. |    .    678      678 |
     |----------------------|
  6. |    .    678      678 |
  7. |    .    678      678 |
  8. |    .    678      678 |
     +----------------------+

It should not change the value of -var1-. If that happens, your copy of Stata is corrupted. 

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

Lucie Vlach

I need to create a new variable that will copy data from other variables (2 or more) and combine them into the new one. The existing vars will only have a number or missing value.
I found something similar on this list, and I tried:

gen newvar = max(var1, var2) if missing(var1, var2)

But it's changing the value of var1.
I would like to see the newvar look like this:

SAMPLE DATA:
var1  var 2   newvar
345    .        345
345    .        345
345    .        345
345    .        345
.       678     678
.       678     678
.       678     678
.       678     678
ETC
(I use Stata/IC 11.2)


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