Re: [eigen] How can I improve this function
• To: eigen@xxxxxxxxxxxxxxxxxxx
• Subject: Re: [eigen] How can I improve this function
• From: Gael Guennebaud <gael.guennebaud@xxxxxxxxx>
• Date: Sat, 22 Sep 2012 23:17:52 +0200
• Dkim-signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:in-reply-to:references:from:date:message-id:subject:to :content-type; bh=IOhB3I3Ve8B1Nx3Omwn3Hmgtb4fQDPY2Ss9xY3pF4kQ=; b=aG6C588Li8IeJKVWRceLCuXEMmy/b8uVtYm0z2teHQKOfZAHtZj/cZLFm5K9+kKsXb eOpDa6/x1iAkobgIp6KxXMwO2ppvDdGTIuuSpDPEsihYKf6VSEdxhEfKl49V1BxLkPS+ XeYlfcs9gBtXy4+JHs9xtWSB4vtRxyCNPurqV4fJdGF5jX17kuKaRcDejLV1B1LGm+wJ qrxGA5AlGNLMNWLoy9fpDe3S4iXx9WDggjItLMk1c9xbrd2OUG9FVwf5tQM5vcFZbMw1 TdI4D8JJsiPUA9hP+fECyayZn7mmtGrCznK/OG9gQG20/lj+jEVy/XmAe0cTE66y9qTg obsw==

``` you could try:

x = (x.array()>0).select(xval, (y.array()>0).select(yval, x) );

but that won't be faster.

gael

On Sat, Sep 22, 2012 at 1:54 AM, Hung Dang <hungptit@xxxxxxxxx> wrote:
> Hi all,
>
> I have below function and I would like to improve it using Eigen's way. Any
> suggestion?
>
> Thanks a lot
> Hung
>
>   template<typename T>
>   void combine(Eigen::Matrix<T, Eigen::Dynamic, 1> & x, const T xval,
>            const Eigen::Matrix<T, Eigen::Dynamic, 1> & y, const T yval) {
>     const size_t len = x.rows();
>     for (size_t idx = 0; idx < len; idx ++) {
>       if (x(idx,0) > 0) {
>     x(idx,0) = xval;
>       } else {
>     if (y(idx,0) > 0) x(idx,0) = yval;
>       }
>     }
>   }
>
>
>

```

 Mail converted by MHonArc 2.6.19+ http://listengine.tuxfamily.org/