CUDT: A CUDA Based Decision Tree Algorithm

Algorithm 6

Algorithm of partition.

Algorithm Partition

Input:  Target array 𝐴

        A flag array with 0, 1 Flag

        A Set of attribute lists 𝐴

(1)  Declare max = sizeof(𝐴)

(2)  Declare buffer[max]

(3)  Declare FalseArray[max]

(4)  Declare TotalFalse

(5)  Declare Address[max]

(6)  For each element 𝑖 in Flag[]  do in parallel

(7)    buffer[𝑖] = !Flag[𝑖]

(8) FalseArray[]← Scan(buffer[])

(9) TotalFalse = InverFlag[max] + FalseArray[max]

(10) For each element 𝑖 in buffer[]  do in parallel

(11)    buffer[𝑖] = 𝑖  − FalseArray[𝑖] + TotalFalse

(12)    Address[𝑖] = (Flag[𝑖] == 0) ? FalseArray[𝑖]: buffer[𝑖]

(13) For each element 𝑖 in 𝐴[]  do in parallel

(14)    buffer[𝑖] = 𝐴[𝑖]

(15)     𝐴[Address[𝑖]] = buffer[𝑖]