search for: beforetran

Displaying 1 result from an estimated 1 matches for "beforetran".

2010 Jun 03
2
lapply or data.table to find a unit's previous transaction
...with(Data, ??Data[ ??UnitID== substr(x, 1, nchar(n))& ??TranDt< Data[TranID== x, "TranDt"], ] ??)) ??) #I do get warnings about missing data because some transactions have no predecessor. #Some transactions have no previous transactions, others have many so I pick the most recent BeforeTran<- lapply(seq_along(PreTran), function(x) ( with(PreTran[[x]], PreTran[[x]][which(TranDt== max(TranDt)), ]))) #I need to add the current transaction's TranID to the list so I can merge later BeforeTran<- lapply(seq_along(PreTran), function(x) ( transform(BeforeTran[[x]], TranID= TranList...