Data representation in a specific format

Hi

I am working on a large data set which I need to convert in a specific format for further processing. I am looking for your advice in this regard.

Sample data

A=[0.99 -0.99
     1       -1
     0.55   -0.55]

Sample output:

val(:,:,1,1)=0.99
val(:,:,2,1)=-0.99
val(:,:,1,2)=1
val(:,:,2,2)=-1
val(:,:,1,3)=0.55
val(:,:,2,3)=-0.55

During working on this, I found a code inside a cnn toolbox of matlab r2018b

function dummifiedOut = dummify(categoricalIn)
    % iDummify   Convert a categorical input into a dummified output.
    %
    % dummifiedOut(1,1,i,j)=1 if observation j is in class i, and zero
    % otherwise. Therefore, dummifiedOut will be of size [1, 1, K, N],
    % where K is the number of categories and N is the number of
    % observation in categoricalIn.
    
    %   Copyright 2015-2016 The MathWorks, Inc.
    
    numObservations = numel(categoricalIn);
    numCategories = numel(categories(categoricalIn));
    dummifiedSize = [1, 1, numCategories, numObservations];
    dummifiedOut = zeros(dummifiedSize);
    categoricalIn = iMakeHorizontal( categoricalIn );
    idx = sub2ind(dummifiedSize(3:4), int32(categoricalIn), 1:numObservations);
    dummifiedOut(idx) = 1;
end
function vec = iMakeHorizontal( vec )
    vec = reshape( vec, 1, numel( vec ) );
end

Can we modify this block of code in such a way to produce the sample output?

I am looking for your advice.

thanks,

[Walter Roberson]

You write to the same location multiple times.

Are your two values always exact negatives of each other?

[Saugata Bose]

walter hi

most of the time, data appears exact opposite of the first one.

thanks,

Answer 1

[Walter Roberson]

val = repmat(permute(A, [4 3 2 1]), num_rows, num_cols, 1, 1);

where num_rows is the number of rows you want for val(:,:,1,1) and num_cols is the number of columns you want for val(:,:,1,1)

[Saugata Bose]

@Walter Roberson

thanks for ur suggestion. Though I understand how this code block works yet, I need to understand if I am looking for such a following output, what changes the code block may demand? Could you please highlight this issue?

Sample output:

val(:,:,1,1)=0.99
val(:,:,2,1)=-0.99
val(:,:,3,1)=0
val(:,:,4,1)=0
val(:,:,1,2)=1
val(:,:,2,2)=-1
val(:,:,3,2)=0
val(:,:,4,2)=0
val(:,:,1,3)=0.55
val(:,:,2,3)=-0.55
val(:,:,3,3)=0
val(:,:,4,3)=0

[Walter Roberson]

A = [0.99 -0.99 0 0
     1    -1    0 0
     0.55 -0.55 0 0
    ]

together with the code I posted.