numpy.dot() result different with classic computation for large-size arrays

[geekgeek]

Thanks to Gribouillis, casevh, paul18fr.

Do we have a good way to raise overflow exception in python? As the code just silently use the overflown values, sometime we are not even aware of what is going on .

I didn't do much python programming, so not sure what is feasible or not.

Thanks.