DurationCombined
DurationCombined is a metric used in time-based analysis to describe the total span of time covered by a set of intervals, counting overlapping portions only once. Formally, given a collection of intervals [s_i, e_i] with s_i < e_i, durationCombined equals the length of the union of these intervals: length(∪_i [s_i, e_i]). In discrete time, it is the number of time units that belong to at least one interval. This makes durationCombined distinct from the sum of durations, which counts overlaps multiple times.
Computation is commonly performed with a sweep-line approach. Collect all interval endpoints, sort them by time,
Examples: Intervals (0,4), (2,6), (7,8) yield durationCombined 7, since the union of the first two is [0,6]
Applications include project scheduling, multimedia editing, log analysis, and sensor data processing, where it is useful