python append方法在大量數據加入list時的效率對比.

def app1(count):
    a=[]
    for i in range(count):
    for j in range(10000):
    a.append((i,j))
    return a

def app2(count):
    a=[]
    fun_app = a.append
    for i in range(count):
    for j in range(10000):
    fun_app((i,j))
    return a

def run(count):
    time1 = time.time()
    app1(count)
    time2 = time.time()
    print "time app1:",time2-time1
    time3 = time.time()
    app2(count)
    time4 = time.time()
    print "time app2:",time4-time3

>>> run(10)

time app1: 0.0699999332428

time app2: 0.0269999504089

>>> run(100)

time app1: 0.394000053406

time app2: 0.313999891281

>>> run(1000)

time app1: 4.13199996948

time app2: 3.27199983597

說明:

    函數中對list的方法賦與臨時變量, 實測效率有所提升, 緣由有高人說說嗎