st: RE: make use of values of some variables to identify another variable

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

Your idea could be made to work like this: 

gen variable_new = . 

qui forval i = 1/`=_N' { 
	local var1 = var1[`i'] 
	local var2 = var2[`i'] 
	local var3 = var3[`i'] 
	local var4 = var4[`i'] 
	replace variable_new = cod_`var1'`var2'`var3'`var4' * sqrt(var5) in `i' 
} 

That's not going to be very fast, but it's perhaps more transparent than alternatives. 

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

N.B. please send your winmail.dat to the list: see the FAQ. 

Maria Dolores Montoya Diaz

I�m trying  to make use of the combination of the values of four variables
(var1-var4) to identify another variable among a big list, which content
will be part of another operation. The situation is:

                 var1   var2  var3      var4 ...   cod_0001     cod_0002
.....  cod_1032
obs 1         1          0        3          2    ...    0.2435
0.5572       .....    0.3453
obs 2         0          0        0          1    ...    0.0632
0.1023       .....    0.5532
   :            

So, for obs 1, the variable selected will be cod_1032, for obs 2, cod_0001,
and so on. I need to do something like this: 

gen variable_new = cod_`var1'`var2'`var3'`var4' *  sqrt(var5)


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