Numpy ufunc.at()

xor-tri-matrix.py

"""
Initiating a 9000x9000 triangular matrix and applying XOR across all elements
"""

""" Using ufunc without at()  """
%%timeit
a = np.tri(9000,dtype=int)
a = np.bitwise_xor(a,1)
# 1 loops, best of 3: 373 ms per loop

""" Using simple incrementing assignment faster than ufunc """
%%timeit
c = np.tri(9000, dtype=int)
c ^= 1
# 1 loops, best of 3: 270 ms per loop

""" at() is tremendously slower than either methods above """
%%timeit
a = np.tri(9000,dtype=int)
np.bitwise_xor.at(a,None,1)
# 1 loops, best of 3: 8.13 s per loop