diff get

diff_get.py

def difficulty(c):
    execute(c, "SELECT block_height, timestamp FROM transactions WHERE reward != 0 ORDER BY block_height DESC LIMIT 2")
    block_height, timestamp_last = c.fetchone()
    timestamp_before_last = c.fetchone()[1]

    execute_param(c, "SELECT timestamp FROM transactions WHERE block_height > ? AND reward != 0 ORDER BY timestamp ASC LIMIT 2", (block_height - 1441,))
    timestamp_1441 = c.fetchone()[0]
    block_time_prev = (timestamp_before_last - timestamp_1441) / 1440
    timestamp_1440 = c.fetchone()[0]
    block_time = (timestamp_last - timestamp_1440) / 1440
    execute(c, "SELECT difficulty FROM misc ORDER BY block_height DESC LIMIT 1")
    diff_block_previous = c.fetchone()[0]

    time_to_generate = timestamp_last - timestamp_before_last

    hashrate = pow(2, diff_block_previous / 2.0) / (block_time * math.ceil(28 - diff_block_previous / 16.0))
    # Calculate new difficulty for desired blocktime of 60 seconds
    target = 60.0
    difficulty_new = (2 / math.log(2)) * math.log(hashrate * target * math.ceil(28 - diff_block_previous / 16.0))
    # Feedback controller
    Kd = 10
    difficulty_new = difficulty_new - Kd * (block_time - block_time_prev)
    diff_adjustment = (difficulty_new - diff_block_previous) / 720  # reduce by factor of 720

    if diff_adjustment > 1:
        diff_adjustment = 1

    difficulty_new_adjusted = diff_block_previous + diff_adjustment
    difficulty = difficulty_new_adjusted

    # Tail Removal Code
    diff_drop_time = 180

    if time.time() > timestamp_last + diff_drop_time:
        time_difference = time.time() - timestamp_last
        diff_dropped = difficulty - time_difference / diff_drop_time
    else:
        diff_dropped = difficulty
    # End Tail Removal Code
    
    if difficulty < 50:
        difficulty = 50
    if diff_dropped < 50:
        diff_dropped = 50

    return (difficulty, diff_dropped, time_to_generate, diff_block_previous, block_time, 
            hashrate, diff_adjustment, block_height)