Comparing multiple numpy arrays

For three arrays, you can check for equality among the corresponding elements between the first and second arrays and then second and third arrays to give us two boolean scalars and finally see if both of these scalars are True for final scalar output, like so -

np.logical_and( (a==b).all(), (b==c).all() )

For more number of arrays, you could stack them, get the differentiation along the axis of stacking and check if all of those differentiations are equal to zeros. If they are, we have equality among all input arrays, otherwise not. The implementation would look like so -

L = [a,b,c]    # List of input arrays
out = (np.diff(np.vstack(L).reshape(len(L),-1),axis=0)==0).all()

For three arrays, you should really just compare them two at a time:

if np.array_equal(a, b) and np.array_equal(b, c):
    do_whatever()

For a variable number of arrays, let's suppose they're all combined into one big array arrays. Then you could do

if np.all(arrays[:-1] == arrays[1:]):
    do_whatever()