NISHIO Hirokazu[日本語][English]

numpyの添え字アクセスは遅い

添え字指定でのランダムアクセスを繰り返すようなアルゴリズムに関してはnumpy.arrayにするよりリストのままの方が速い python

In [71]: %%timeit
    ...: xs = np.zeros(100)
    ...: xs[0]
    ...: 
696 ns ± 4.94 ns per loop (mean ± std. dev. of 7 runs, 1000000 loops each)

In [72]: %%timeit
    ...: xs = [0] * 100
    ...: xs[0]
    ...: 
416 ns ± 3.79 ns per loop (mean ± std. dev. of 7 runs, 1000000 loops each)

(C)NISHIO Hirokazu / Converted from Markdown (ja)
Source: [GitHub] / [Scrapbox]