loadind data loop fastly?

Hi everybody, Please i have this code that load data too long time, i want to read it fastly(reduce time execution), somebody can i help me?

%Data is the 381x247x3 matrix; if true

    LastGood = floor((122.5 - 50) / Header.Fstep) + 1 - 1; % value =29
    FirstGood = ceil((140 - 50) / Header.Fstep) + 1 + 1;  % value =38
    disp(LastGood); % value =29
    disp(FirstGood); % value =38
    disp(size(Data, 2)); % value =247
    for(k = 1:size(Data, 2))
        InterpolazioneReale1 = fit(cat(2,[1:LastGood],[FirstGood:381])',cat(1,real(Data(1:LastGood,k,1)),real(Data(FirstGood:end,k,1))),'splineinterp');
        InterpolazioneReale2 = fit(cat(2,[1:LastGood],[FirstGood:381])',cat(1,real(Data(1:LastGood,k,2)),real(Data(FirstGood:end,k,2))),'splineinterp');
        InterpolazioneReale3 = fit(cat(2,[1:LastGood],[FirstGood:381])',cat(1,real(Data(1:LastGood,k,3)),real(Data(FirstGood:end,k,3))),'splineinterp');
        InterpolazioneImmaginaria1 = fit(cat(2,[1:LastGood],[FirstGood:381])',cat(1,imag(Data(1:LastGood,k,1)),imag(Data(FirstGood:end,k,1))),'splineinterp');
        InterpolazioneImmaginaria2 = fit(cat(2,[1:LastGood],[FirstGood:381])',cat(1,imag(Data(1:LastGood,k,2)),imag(Data(FirstGood:end,k,2))),'splineinterp');
        InterpolazioneImmaginaria3 = fit(cat(2,[1:LastGood],[FirstGood:381])',cat(1,imag(Data(1:LastGood,k,3)),imag(Data(FirstGood:end,k,3))),'splineinterp');
        Data(LastGood + 1:FirstGood - 1,k,1) = InterpolazioneReale1(LastGood + 1:FirstGood - 1) + i * InterpolazioneImmaginaria1(LastGood + 1:FirstGood - 1);
        Data(LastGood + 1:FirstGood - 1,k,2) = InterpolazioneReale2(LastGood + 1:FirstGood - 1) + i * InterpolazioneImmaginaria2(LastGood + 1:FirstGood - 1);
        Data(LastGood + 1:FirstGood - 1,k,3) = InterpolazioneReale3(LastGood + 1:FirstGood - 1) + i * InterpolazioneImmaginaria3(LastGood + 1:FirstGood - 1);
    end
  end

[per isakson]

Make a minimal working example, MWE. This MWE should focus one your question.

We cannot run your m-files without the m-files called, data files and furthermore we don't know what speed you expect.

[KSSV]

It depends on what data your text file has....post your text file....to get help.

[per isakson]

"loadind data loop fastly" How do you currently load/read the data files? Your way might be as fast as it gets.

[Rik]

Sometimes you can even wee it in task manager: if your disk load is 100%, further optimizing your code will not yield any benefit.

[Jan]

Note:

cat(2,[1:LastGood],[FirstGood:381])'

can be simplified to:

[1:LastGood, FirstGood:381]'

Then store this in a variable instead of creating it 6 times.

Performing 6 spline fits for the same locations seems rather inefficient. Could this be simplified?

[denis bertin]

Hi JAN SIMON, Yes, could be simplified, but i don't know how! I changed cat(2,[1:LastGood],[FirstGood:381])' to one variable [1:LastGood, FirstGood:381]', there is just a few change performance.

Thank you.

Answer 1

[OCDER]

Not sure if this is faster or not, but your code could be simplified a lot. If you have parallel computing toolbox, you could divide slow jobs across N cores.

    LastGood = floor((122.5 - 50) / Header.Fstep) + 1 - 1; % value =29
    FirstGood = ceil((140 - 50) / Header.Fstep) + 1 + 1;   % value =38
    disp(LastGood);     % value = 29
    disp(FirstGood);    % value = 38
    disp(size(Data, 2));% value = 247

    X = [1:LastGood, FirstGood:381]';
    parfor z = 1:3
        Tdata = Data(:, :, z);
        for k = 1:size(Tdata, 2) %Or do parfor here instead
            InterpReal = fit(X, real(Tdata(X, k)), 'splineinterp');
            InterpImag = fit(X, imag(Tdata(X, k)), 'splineinterp');
            Range = LastGood + 1:FirstGood - 1;
            Tdata(Range, k) = InterpReal(Range) + 1j * InterpImag(Range); %NOTE: 1j is now sqrt(-1)
        end
        Data(:, :, z) = Tdata;
    end

[denis bertin]

Many Thank's DONALD LEE.

[OCDER]

You're welcome!