
[mg6134] Re: [mg6120] selecting from lists
Posted:
Feb 23, 1997 12:17 AM


Murray Eisenberg wrote:
> The problem: given an arbitrary list v and a list b of the same > length, whose entries are all Boolean (True or False), construct a > function s[v, b] whose result is a list consisting only of those > entries of v for which the corresponding entries in b are True. For > example, > > v = {3, 82, 7, 12, 5}; > b = {False, True, True, False}; > s[v, b] > {82, 7}
How about
s[v_, b_] := Cases[Transpose[{v, b}], {x_, True} > x] Lou Talman

