st: RE: replacing values in a variable with rowsums, aka "ereplace"

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

An -ereplace- would let you use -egen- functions to -replace- variables.


There is no -ereplace- in the public domain. 

I looked in my files and found that I wrote one in 1998, but I don't use
it myself and I've decided that there is little gain. Other programmers
might have similar stories. 

For your problem, just use two statements rather than one:  

egen rowtotal = rowtotal(d2-d40) 
replace x = rowtotal if y == 2 

Note the == in the second statement. 

Martin Weiss has suggested that you look at -cond()-. That's a good
function to know about, but you can't use -rowtotal()- within -cond()-
as -rowtotal()- is an -egen- function. But it still might be useful for
your problem. 

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

Ora John Reuter

I am searching for something that would do the equivalent of an 
'ereplace'.  I have a set variables for which I generated a -rowtotal- 
given some condition, e.g. (egen x=rowtotal (d1-d40) if y=1), but then 
I need to replace some values in that same variable (x) with a 
different -rowtotal- given a different condition.  I dont know how else 
to explain it except to say that if there were an  'ereplace' command 
the next command would look like this:

"ereplace" x=rowtotal(d2-d40) if y=2

In other words, I need to replace values in x with different sums of 
variables.  I need to do this for a great many conditions so typing out 
the list of variables to be added for each condition would be a minor 
pain.


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