st: Re lincom not recognising macros

[Jennifer Dent <JDent@sgul.ac.uk>]

I'm trying to run lincom in stata 12 but I am having trouble when I use 
a marco name, rather than a number.

This is what I have:

gen var1_prop =  0.46
gen var2_prop = 0.54
xi:xtmixed depvar indep1 indep2 || randomeffect
lincom _b[_cons] + _b[indep1]*var1_prop + _b[indepvar2]*var2_prop

Error: var1_prop not found

If I replace var1_prop and var2_prop with the actual numbers (i.e. 
lincom _b[_cons] + _b[indep1]*0.46 + _b[indepvar2]*0.54), then stata is 
happy. Is there a way to force lincom to recognise my numeric macors by 
name, rather than to have to find and replace the names with numbers?

Many thanks in advance,

Jennifer
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