Composition Analysis and Feature Selection of the Oral Microbiota Associated with Periodontal Disease

Algorithm 1

The prioritized feature combination-generated algorithm was used to generate all combinations of selected features in prioritized order. As an example, when equals four, the generated list will be (1000, 0100, 1100, 0010, 1010, 0110, 1110, 0001, 1001, 0101, 1101, 0011, 1011, 0111, 1111). Each element is a combination and denotes whether the four features were selected in that combination (e.g., the combination containing the first and third features is represented as 1010).

GenPFC()   Generate prioritized feature combinations.

Input: () a list with features in prioritized order.

Output: a queue used to store feature combinations.

1    Enqueue empty set into queue

2 for    to    do   Generate attribute combinations according to features in the list.

3    Copy into which is a temporary queue.

4 for each in   do

5 Enqueue

6 Dequeue   Delete first empty set from queue

7 return