Re: List complement operator
- To: mathgroup at smc.vnet.net
- Subject: [mg85086] Re: List complement operator
- From: Szabolcs Horvát <szhorvat at gmail.com>
- Date: Sun, 27 Jan 2008 05:50:47 -0500 (EST)
- Organization: University of Bergen
- References: <fn1ndi$97t$1@smc.vnet.net> <fn21s3$irs$1@smc.vnet.net> <fneson$i6c$1@smc.vnet.net>
zac wrote:
> I'm extremely sorry to post my code with undefined function RDI.
> RDI[x] is simply my shorthand version of Random[Integer, {1, x}],
> which is defined by a package I use all the time. I hope it clears
> everything.
With this specific input (very few different elements, 10 in your
example), you can get a massive (more than 10x) speed boost from changing
u = Union[a, b]
in my version to
u = Sort[Tally[Join[a,b]][[All, 1]]]
(I mentioned this possibility in another message.)
But it still won't be nearly as fast as Oleksandr Pavlyk's version.
Szabolcs