The elements of the array given to the constructor can be randomly picked with weights according to the probabilityWeight property of each element.
Computational Complexity
| Function | Complexity |
|---|---|
| constructor | O(N) |
| update | O(log N) |
| pick | O(log N) |
Usage
final picker = WeightedRandomPicker(entities);
print(picker.pick().id);
picker.elements.probabilityWeight = 10;
picker.update(2);
print(picker.pick().id);
Performance Test
Class Creating
10000x100: 0:00:00.314480
20000x100: 0:00:00.703230
30000x100: 0:00:00.737919
40000x100: 0:00:01.534356
50000x100: 0:00:01.566525
60000x100: 0:00:01.627591
70000x100: 0:00:03.316556
80000x100: 0:00:03.690221
90000x100: 0:00:03.526130
Picking
1000000x100: 0:00:00.000839
2000000x100: 0:00:00.079502
3000000x100: 0:00:00.000440
4000000x100: 0:00:00.000629
5000000x100: 0:00:00.000357
6000000x100: 0:00:00.000454
7000000x100: 0:00:00.000348
8000000x100: 0:00:00.000787
9000000x100: 0:00:00.000528
Updating
1000000x100: 0:00:00.000371
2000000x100: 0:00:00.000089
3000000x100: 0:00:00.000101
4000000x100: 0:00:00.000030
5000000x100: 0:00:00.000036
6000000x100: 0:00:00.000063
7000000x100: 0:00:00.000032
8000000x100: 0:00:00.000029
9000000x100: 0:00:00.000031