Re: [eigen] Eigen appears to rock.
• To: eigen@xxxxxxxxxxxxxxxxxxx
• Subject: Re: [eigen] Eigen appears to rock.
• From: "Gael Guennebaud" <gael.guennebaud@xxxxxxxxx>
• Date: Fri, 22 Aug 2008 19:09:21 +0200
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```On Fri, Aug 22, 2008 at 5:53 PM, Thomas Vaughan <tevaughan@xxxxxxxxx> wrote:
> On Fri, Aug 22, 2008 at 7:51 AM, Gael Guennebaud
> <gael.guennebaud@xxxxxxxxx> wrote:
>>
>> but what about more general weighted mean of a set of points:
>>
>> for(i) {
>>  m += p[i] * weight[i];
>>  sumW += weight[i];
>> }
>> m /= sumW;
>
> It seems that your p is really a displacement vector.

ah yes I was not very clear when I wrote: "let's assume p = p-0". What
I really meant is to indeed consider "p=p-0", and then completely
forget about Points and only deal with Vectors (and "displacement
vectors"). In that case you only need to make the distinction when you
apply the transformation, and the rest remains sounds. But, yes, I
agree that in that context "T * a" remains the only thing which is not
very beautiful but it is so convenient !

gael.

```

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