Re: Please, help me vectorize this code

[Pablo Fernández Bustamante]

17/09/17 16:45(e)an, Giovanni Ciriani igorleak idatzi zuen:
> The correct code is
> M .* (M>4)

Thank you, Giovanni! This is so much simpler and faster!

Thank you, Michele and Zoltan.

Regards,
Pablo


> On Sun, Sep 17, 2017 at 10:08 AM, michele <address@hidden 
> <mailto:address@hidden>> wrote:
>
>     On 09/17/2017 01:15 PM, Pablo Fernández Bustamante wrote:
>
>         Hi,
>
>         I want the elements of a matrix M_ to be equal to those of an
>         original matrix M but only if they satisfy a certain condition,
>         otherwise write a zero.
>
>         The following lines of code work as expected but I want to avoid the
>         loop if it is possible.
>
>          >> M = floor(rand(5, 4)*10);
>          >> [r, c] = find(M > 4);
>          >> M_ = zeros(5, 4);
>          >> for n = 1:length(r)
>         M_(r(n), c(n)) = M(r(n), c(n));
>         endfor
>
>         I have tried
>
>         M_ = M(find(M>4));
>
>         but that returns a column vector of the elements which satisfy
>         the condition.
>
>         Thanks in advance,
>
>         Pablo
>
>
>
>
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>
>
>     You can do like this:
>
>     M = floor(rand(5,4)*10);
>     M1 = zeros(5,4);
>     M1(M>4) = M(M>4);
>
>     Bests,
>
>     -- 
>     Michele Ginesi
>
>
>
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