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random - How can I randomize order of elements in a list?


Is there a straightforward way to go from an ordered list like:


ord = {a, b, c, d, e, f, g, h}


to a disordered list like:


randompos = {c, h, d, g, a, b, f, e}

I can certainly use something like:


DeleteDuplicates @ RandomChoice[ord, 50]

but this is not really robust.


Is there an easier way?



Answer







as @Spawn1701D and @Oleksandr R.said in comment,


RandomSample[ord] is sufficient.


ord = {a, b, c, d, e, f, g, h};

RandomSample[ord]

(*
{c,e,g,b,h,f,a,d}

*)

To get one sublist


RandomSample[#, Length[#] - 4] & @ ord

(*
{g,h,e,f}
*)





SeedRandom[1234]; Permute[ord, RandomPermutation[8]]

(*
{b,f,e,h,d,g,c,a}
*)

One aside: sometimes when people's comments are apparently feasible to the question, they might not likely to answer the post, others may wish the first people who leave the good comment to answer the question, and OP is also encouraged to answer its own question.


So I answer the little post with one additional method.


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