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dpb
Posts:
9,850
Registered:
6/7/07


Re: Matrix dimensions must agree.
Posted:
Mar 21, 2014 11:40 AM


On 3/21/2014 8:46 AM, Steven Lord wrote: > "Vitor Andrade" <vitor.luiz.de.andrade@gmail.com> wrote in message > news:lghenc$13g$1@newscl01ah.mathworks.com... ... >>> dpb <none@non.net> wrote in message <lgfaqk$820$1@speranza.aioe.org>... >>> > On 3/20/2014 12:57 PM, Vitor Andrade wrote: > ...
>>>> if x > y a(y+1:end,:)=[]; ... >> elseif y > x b(x+1:end,:)=[]; end ...
> > I wouldn't use this approach; I'd instead select the elements to keep. > It avoids the IF and ELSEIF statements at the expense of a call to MIN: > > minRows = min(x, y); > a = a(1:minRows, :); > b = b(1:minRows, :); > ...
It then also has the cost of the selection on both where one is already ok that the if...elseif avoids which is why I went that route.
My _real_ suggestion/hope was that Vitor would rethink his generation process and avoid the problem at the start instead of having to fix it up afterwards.
I also wrote the example for vectors illustrating the idea (hence length() and linear addressing) but I suppose expecting the extrapolation to an array was too much of leap of faith for the neophyte :)




