[Trisquel-users] Re : Scripting the random replacement of fields in an IPv6 address

[lcerf]

It appears not to produce any "000x", "00xx" or "0xxx" fields, which do occur  
in real IPv6 addresses.

Indeed.  The probability distribution is uniform.  To sample an hexadecimal  
number (with at most four digits) according to a Zipf distribution (probably  
what you want), you should abandon simple commands and find an implementation  
in your favorite programming language.  For instance, I know C++ and  
searching the Web for "sample Zipf C++" gave  
https://stackoverflow.com/questions/9983239/how-to-generate-zipf-distributed-numbers-efficiently  
as the first result.