6 ms·
If you have repetitive data in, and repetitive data out, no modulus is going to help you. Um, no. A prime modulus will often help in this case. That's the wh
by calambrac 17y ago
If you have repetitive data in, and repetitive data out, no modulus is going to help you.
Um, no. A prime modulus will often help in this case. That's the whole point.
- codexon 17y agoDo you have any statistical evidence?
- calambrac 17y agoIn your test code, change your loop to: for r in [3, 5, 17, 257]: for i in xrange(n): num = r * i table_p[num%prime] += 1 table_c[num%composite] += 1 On here and on your blog, you keep falling back to the observation that modulo prime makes no difference when you have a uniform distribution of inputs, like you get after you apply a good hash function. Nobody who is telling you that you're wrong would dispute that. The fundamental point that you keep ignoring is that doesn't matter, because as a library writer providing a hashtable, you don't control the hash function. Having a simple way to mitigate the ill effects of users choosing bad hash functions is a good thing. Why do you keep ignoring this point?