st: RE: RE: Making a local with no assigned value zero

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

4. 

local x1 = `y1' + `x1' 

(doesn't fit all problems, but might fit yours)

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

Nick Cox

There are various fixes. Here are some: 

1. 

if "`y1'" == "" local y1 = 0 
local x1 = `x1' + `y1' 

2. 

local x1 = cond("`y1'" != "", `x1' + `y1', `x1') 

3. 

if "`y1'" != "" local x1 = `x1' + `y1' 

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

George Chioran
 
My code goes like
this: local x1 = `x1’ + `y1’. I get the `y1’ variable through repeated loops
and sometimes `y1’ is not assigned any value. 
When `y1’ does not
have any value, the line local x1 = `x1’ + `y1’ stops my program and I get an invalid
syntax error. 
 
My question is: Could
I somehow make the local `y1’ to be equal to zero, or not to be taken into
consideration in my sum in case `y1’ is not assigned any value? 
 

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