[Top][All Lists]

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: My vectorized code is slower than a loop

From: Andreas Weber
Subject: Re: My vectorized code is slower than a loop
Date: Tue, 18 Oct 2016 19:38:12 +0200
User-agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Icedove/45.2.0

Am 17.10.2016 um 21:37 schrieb Dave Cottingham 2:
> In the process of writing a routine to compute the Qn statistic of Croux and
> Rousseeuw, I started from the Fortran code they published in their paper
> (C&R, "Time-efficient algorithms for two highly robust estimators of scale")
> and ran into unexpected trouble with one section. Here's a fairly literal
> translation of the original, where x is an array of length n, and left and
> right are also arrays of length n that contain integers:
> code snipped

Your script can be simplified to

w = x-x(end:-1:1);

try it out!

Since "if(left(i) <= right(i))" is always true. Perhaps you can provide
a realistic example?

-- Andy

reply via email to

[Prev in Thread] Current Thread [Next in Thread]