s(y).sum(axis=1)
array([ 1.2       ,  1.27041742,  0.92658316])  # may vary

>>> permscale  # only powers of 2 (0.5 == 2^(-1))
array([[  0.5,   0. ,  0. ],  # may vary
       [  0. ,   1. ,  0. ],
       [  0. ,   0. ,  1. ]])

TrE