if I take the result of a 32bit hash function(the param is random string) and apply module N on the result - will the values be evenly distributed?
so if I have a histogram of values [0,N-1] will the histogram be evenly distributed ?
Thanks
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if I take the result of a 32bit hash function(the param is random string) and apply module N on the result - will the values be evenly distributed?
It depends on the hash function. For a good hash function the output should be uniformly distributed.
so if I have a histogram of values [0,N-1] will the histogram be evenly distributed ?
For any reasonable hash function, yes.
Keep in mind that real-world hash functions are sometimes terrible. Many programming languages will, as the hash of an integer (using the built-in hashing function), return the original value. This is not a problem if your input is truly random, but usually the reason to use a hash function is to take an input that has some structure, and produce hashes that (hopefully) don't.
answered May 4, 2019 at 6:47
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$\begingroup$ I edited my post - I didnt meant to say that its 'exactly' 10 values of each but 'more or less'.. so just to verify your answer - if the hash function is uniformly distributed so applying modulo on the result will still be uniformly distributed? $\endgroup$– nadavgamCommented May 4, 2019 at 15:54