st: Invalid Syntax

[Amir Sadeghi Emamgholi <asadeghi@gwmail.gwu.edu>]

Hello Statalisters,

Sorry for this stupid question. I cannot figure out the problem with
my drop command in the following loop. When I run it I get the -
Invalid Syntax - error message.

The loop:

foreach i in E_I3 E_I4 E_I5 E_I6 E_I7 E_I8 E_I9 E_I10 E_I11 {
      qui summ `i'
      drop `i' if r(N) == 0
}

Thanks!
Amirsa

P.S. when I use - drop "`i'" if r(N) == 0 - I get the - "E_I3 invalid
name - error message.
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