Re: Logical comparisons of items in a two lists
- To: mathgroup at smc.vnet.net
- Subject: [mg75458] Re: Logical comparisons of items in a two lists
- From: dh <dh at metrohm.ch>
- Date: Tue, 1 May 2007 05:40:47 -0400 (EDT)
- References: <f16q2u$7er$1@smc.vnet.net>
Hi Larry,
what's wrong with Count? It is pretty efficient. However, you could
speed up the creation of the list a bit by e.g.: Thread[list1 > list2]
or you could use Compilation:
fun=Compile[{{v1,_Real,1},{v2,_Real,1}},Table[Boole[v1[[i]]<v2[[i]]],{i,1,Length[v1]}]];
Total@ fun[list1,list2]
hope this helps, Daniel
actuary at mchsi.com wrote:
> Hello:
>
> I have two lists of real numbers, a & b. I want two compare
> individual items in one list to the corresponding items in the other
> list. For example Is a[[1]] > b[[1]]. At the end of the comparisons,
> I want to count the "Trues". I know how to do this use a "Table"
> statement and a "Count" statement. Is there a quicker, more efficient
> way of counting the number of "Trues".
>
> Thanks
>
> Larry
>
>