def msign(x):
    return ma.filled(np.sign(x), 0)
L{IReactorThreads.callFromThread} can be used to schedule a large
dataset/ETHPy150Open scipy/scipy/scipy/stats/mstats_basic.py/msign--crossover with--dataset/ETHPy150Open kuri65536/python-for-android/python-modules/twisted/twisted/test/test_internet.py/CallFromThreadTestCase.test_lotsOfThreadsAreScheduledCorrectly