st: Replace after egen with conditions

[Miguel Olivo-Villabrille <m.olivo@gmail.com>]

Hi all,

I have a panel data set, I am trying to compute totals by date for
observations that match certain conditions:

bys date2: egen total_supply=total(supply) if dispatched=="Y" & big==1

this will give me what I want but it will only assign that total to
observations that match the conditions. I am interested in producing a
constant variable within dates that has that (total for observations
that match the conditions) but assigned to all observations
regardless. Any ideas how I might accomplish this?
I tried

bys date2: replace total_supply=total_supply[_n-1] if total_supply==.

but that solves the problem for the bottom observations within date,
and not the observations before the condition is met. Also, adding

bys date2: replace total_supply=total_supply[_n+1] if total_supply==.

will only change the one observation before the condition is met

Any suggestions are welcome

Miguel
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