Comparison of item removal techniques in python

plucking.py

import numpy
import numpy.ma
import random
import timeit


def using_del(numbers, indices):
    numbers = numbers[:]
    offset = 0
    for i in indices:
        del numbers[i - offset]
        offset += 1


def using_set(numbers, indices):
    indices = set(indices)
    [x for i, x in enumerate(numbers) if i not in indices]


def using_list(numbers, indices):
    [x for i, x in enumerate(numbers) if i not in indices]


def using_numpy(numbers, indices):
    a = numpy.array(numbers)
    numpy.delete(a, indices)


def using_slices(numbers, indices):
    result = []
    i = 0
    for j in indices:
        result += numbers[i:j]
        i = j + 1
    result += numbers[i:]


def using_masked(numbers, indices):
    numbers = numpy.ma.array(numbers)
    numbers[indices] = numpy.ma.masked


for i in range(15, 25, 1):
    size = 2 ** i
    tests = [
        using_list,
        using_del,
        using_numpy,
        using_set,
        using_slices,
        using_masked,
    ]

    results = []
    for test in tests:
        numbers = range(size)
        # make 1/20 the number of indices
        indices = sorted(set([random.randrange(0, size) for _ in xrange(size / 20)]))
        results.append(timeit.timeit(lambda: test(numbers, indices), number=1))

    print '2^%d' % i, '\t', '\t'.join(map(str, results))