SVD reconstruction of waveforms

I have carried out SVD on 13 different waveforms and formed a matrix of 13 column vectors. Now my job is to multiply the first few modes or columns to reconstruct the waveforms. Can anyone help me with it please.

Answer 1

[Star Strider]

Is this what you want to do?

        a = [0:0.1:6*pi]';
        z1 = [sin(a)  sin(3*a)  sin(5*a)  sin(7*a)];
        z2 = z1(:,1);
        for k1 = 1:size(z1,2)-1
            z2 = z2.*z1(:,k1+1);
        end

        figure(1)
        plot(a, z1, ':')
        hold on
        plot(a, z2, '-r')
        hold off
        grid