[R] with replace na with 0?

[Enrico Gabrielli]

Hello
I almost got through the problem in post "aggregation of irregular
interval time-series"
I just don't understand how to fix that when I try
''
with(datatable,ifelse(is.na(x),y,x))
''
if y is na
replaces me with 0
and not with na

Thank you
-- 
Perito agrario Enrico Gabrielli
Tessera n. 633 Collegio Periti agrari prov. Di Modena
Biblioteca agricoltura: https://www.zotero.org/groups/aplomb/
https://it.linkedin.com/pub/enrico-gabrielli/9a/186/159
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