I am trying to create a function form a vector from my matrix and I do not understand where my mistake is?

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Laurence Guevremont 2016-9-27

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评论： dpb 2016-9-29

    function A=combined (V)
    for V(k)= A(i,j)
        k=1;
        for
            i=1;
            j=1;
            k=k+1;
        end
    end

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Laurence Guevremont 2016-9-27

编辑：Laurence Guevremont 2016-9-27

Ok so I need transform my matrix into a vector so example: A= [1 2 3; 4 5 6; 7 8 9] And then form a vector A A=[1 2 3 4 5 6 7 8 9]

My function right now does not work, there is a mistake on line 2

dpb 2016-9-27

Indeed, there are several issues but the one of defining the for...end loop indices and range is key. To do the requested function, using "linear addressing" would be a good way to proceed. Look those up in the documentation and study for loops...

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Answer 1

Moe_2015 2016-9-27

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编辑：Moe_2015 2016-9-27

在 MATLAB Online 中打开

You should avoid using a for loop here. You can do something like this:

function myVector=combined(myMatrix)
     myVector = reshape(myMatrix,1,numel(myMatrix));
end

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Laurence Guevremont 2016-9-27

But I need to create a function I cannot use one already made by matlab

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Answer 2

dpb 2016-9-27

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"...transform my matrix into a vector"

Really don't need a function for this; Matlab has syntax to do it already. A previous answer shows reshape, except I'd suggest to simply use it ( reshape, that is) inline as shown there in the function instead.

There's another Matlab idiom that's even more compact--

A=A(:).'; % convert A of unspecified dimensions to row vector

NB: the .' transpose operator to return the requested row vector instead of the column vector colon returns.

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Laurence Guevremont 2016-9-27

But I need to create a function I cannot use one already made by matlab

dpb 2016-9-27

Then wrap the above inside the function wrapper. Unless the assignment also requires a loop be used???

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Answer 3

James Tursa 2016-9-28

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Here is an outline of what you need to be using for the for loops (seems to be a requirement for this assignment).

    % Insert any initialization code here
    for i = 1:size(V,1)
        for j = 1:size(V,2)
            % Insert your assignment etc code here
        end
    end