Sum partial datatable as column for another datatable [duplicate]

Answer 1

You can use non-equi join in data.table and then sum points which overlap in the range.

library(data.table)

dt[out, .(start, end, game, player, points), 
         on=.(player, game>=start, game<=end)][
       , .(points = sum(points)), by = .(start, end, player)]

#   start end player points
#1:     1   2    ace      7
#2:     1   2    bob      8
#3:     3   3  casey      2