add_deltas() adds event-to-event deltas in raw and normalized x/y,
distance, and angle for a play-by-play. Sequences are bounded by faceoffs:
each sequence begins at a faceoff, faceoff rows do not look backward across
the boundary, and subsequent events are compared to the most recent prior
valid-spatial event in the same faceoff-bounded sequence. Shootout and
penalty-shot rows (0101/1010) are left as NA and do not serve as
anchors for later rows. When multiple events in a sequence share the same
recorded second, zero-time denominators used internally are replaced by
1 / n, where n is the number of events in that same second within the
sequence.
Arguments
- play_by_play
data.frame of play-by-play(s) using the current public schema returned by
gc_play_by_play(),gc_play_by_plays(),wsc_play_by_play(), orwsc_play_by_plays()
Value
data.frame with one row per event (play) and added columns: eventIdPrev, secondsElapsedInSequence, dSecondsElapsedInSequence, dXCoord, dYCoord, dXCoordNorm, dYCoordNorm, dDistance, dAngle, dXCoordPerSecond, dYCoordPerSecond, dXCoordNormPerSecond, dYCoordNormPerSecond, dDistancePerSecond, dAnglePerSecond