An Asynchronous Periodic Sequential Pattern Mining Algorithm with Multiple Minimum Item Supports for Ad Hoc Networking

Algorithm 2

MAPPrefixSpan (prefix, DB, c_item, min_sup, min_rep, max_per, and max_dis).

Input: prefix prefix, temporal symbolic sequence databases TDB, key item c_item, minimum support min_sup, minimum

repeat count min_rep, maximum period max_per, maximum interference distance max_dis.

()   hash_item〈item_id, (count, tids)〉;

()    FOR each tuple in   DO

()      IF  ,   THEN

()     hash_item[].count++; hash_item[].tid ←  ;

()      IF  ,   THEN

()     //prefix.litemset is the last item of prefix

()     hash_item[].count++; hash_item[].tid ←  ;

()    ENDFOR

()    FOR each key in hash_item  DO

()     IF    THEN delete hash_item[];

()  ENDFOR

()  FOR each key c in hash_item  DO

()    ASPDetector (, hash_item[], _item, prefix, min_sup, min_rep, max_per, max_dis);

()     IF   can be extended to prefix  THEN

()    newprefix ← extend(, prefix);

()     ← Projectdatabase (, );

()    IF  prefix notcontain _item  THEN

()     delete tuples in which not contain _item;

()    IF  min_sup ≤   THEN

()   AP-PrefixspanM(newprefix, , _item, min_sup, min_rep, max_per, max_dis);

() ENDFOR