On May 28, 3:52 pm, Antoon Pardon <apar...@forel.vub.ac.be> wrote: > Op 2009-05-26, Arnaud Delobelle schreef <arno...@googlemail.com>: > > > > > Sumitava Mukherjee <sm...@cognobytes.com> writes: > > >> On May 26, 11:39 pm, Sumitava Mukherjee <sm...@cognobytes.com> wrote: > >>> Hi all, > >>> I need to randomly sample from a list where all choices have weights > >>> attached to them. The probability of them being choosen is dependent > >>> on the weights. > >>> If say Sample list of choices are [A,B,C,D,E] and weights of the same > >>> are [0.895,0.567,0.765,0.890,0.60] when I draw (say 2) samples then I > >>> want the likeliness of them being chosen be in the order : D>A>C>E>B > > > You mean A > D > C > E > B > > >>> In short I mean if prob of a H is .9 and probability of T be 0.1 then > >>> if I draw 10 samples, 9 should be H and 1 should be T. > > >>> I coudn't find a function in the module random that does so. > >>> Please can someone guide me how the above could be implemented [either > >>> through some function which exists and I don't know or pointers to > >>> some code snippets which does so]? > > >>>>>> [Oh, I forgot to mention. I am looking for sampling without > >>>>>> replacement.] > > > If you do sampling without replacement, you need to know the exact > > number of each of A, B, C, D, E in the sample, not just their relative > > frequency. > > As far as I understand, you are given the exact number of each. It is one. > The numbers given are not relative frequencies of appearance but weights > to be attributed for picking them. > > -- > Antoon Pardon
Yes, the numbers are weights attributed for picking them. -- http://mail.python.org/mailman/listinfo/python-list
