maia-util/es6/points_belonging_to_interval.js

Utility math and music functions supporting various applications by Music Artificial Intelligence Algorithms, Inc.

export default function points_belonging_to_interval(
  point_set, a, b, ontimeIdx = 0, durIdx = 3
){
  // Tom Collins 25/10/2011.
  // In
  // point_set Array mandatory
  // a Number mandatory
  // b Number mandatory
  // Out Array
  // For a time interval [a, b), this function will return points from the
  // input point_set that sound during the time interval.

  var L = point_set.length;
  var segment = new Array(L);
  var i = 0;
  var j = 0;
  while (i < L){
    if (
      point_set[i][ontimeIdx] < b &&
      point_set[i][ontimeIdx] + point_set[i][durIdx] > a
    ){
      segment[j] = point_set[i];
      j++;
    }
    if (point_set[i][ontimeIdx] >= b) {
      i = L;
    }
    i++;
  }
  return segment.slice(0, j);
}