Unable to perform assignment because the size of the left side is 1-by-1 and the size of the right side is 1-by-2

Hi, I am unable to understand what the error means and at which line of the code it is directed towards. Can someone help me with this?

Thanks a lot!

This is my code so far :

%% Load dataset and remove data about position of moving platform from array
Data_1 = readtable('RFID_1.csv');
Data_2 = readtable('RFID_2.csv');
Data_3 = readtable('RFID_3.csv');
Data_4 = readtable('RFID_4.csv');

data_1 = table2array(Data_1(:, 1:6));
data_2 = table2array(Data_2(:, 1:6));
data_3 = table2array(Data_3(:, 1:6));
data_4 = table2array(Data_4(:, 1:6));

meansData_1 = zeros(6,1);
figure('Name', 'Phase readings for tag', 'WindowState', 'maximized');
tiledlayout(2,6, 'TileSpacing', 'compact')
%% Start to calculate phase differences

for i=1:6
    x = data_1(i,:);
    x_multidim=[cosd(x); sind(x)];
    x_t=x_multidim';
    nexttile;
    idx = dbscan(x_t,0.1,5); 

    gscatter(x_t(:,1),x_t(:,2),idx,'kr','*');
    title(append('At ', num2str(table2array(Data_1(i,1))),'cm'));

    xlim([-1.2 1.2]);
    ylim([-1.2 1.2]);

    viscircles([0 0],1, 'Color', 'b', 'LineWidth',0.1);

    storeall = double.empty(0,2);
    for j=1:6
        if(idx(j)==1)
            storeall = [storeall;x_t(j,:)];
        end
    end

    storeall_filt=rmoutliers(storeall);
    meansData_1(i,:)=mean(storeall);
    hold on;
    plot(meansData_1(i,1),meansData_1(i,2),'XData','MarkerSize',20,'LineWidth',1.5,'Color','magenta','DisplayName','mean');
end
PhData_1 = atan2d(meansData_1(:,2),meansData_1(:,1));
for k=0:6
    if(PhData_1(k)<0)
        PhData_1(k)=360+PhData_1(k);
    end
end

Answer 1

[Voss]

The error message will tell you which line the error occurred on, but I think it's this one:

meansData_1(i,:)=mean(storeall);

And the error happens because meansData_1 has one column, but storeall has two columns (so mean(storeall) has two columns).

To fix it, initialize meansData_1 to have two columns before the for loop:

meansData_1 = zeros(6,2); % instead of zeros(6,1)

Then you will get another error a couple of lines later with the plot call because of an extraneous 'XData' argument that should be removed:

plot(meansData_1(i,1),meansData_1(i,2),'MarkerSize',20,'LineWidth',1.5,'Color','magenta','DisplayName','mean')

[Divya]

Made the changes and ran the code, the previous error was mitigated. But now I am getting "Array indices must be positive integers or logical values "

[Voss]

I guess that new error is on this line:

if(PhData_1(k)<0)

and it happens when k is zero, because indexing in MATLAB starts at one.

Try changing all of this:

for k=0:6
  if(PhData_1(k)<0)
      PhData_1(k)=360+PhData_1(k);
  end
end

to this:

for k = 1:numel(PhData_1)
    if PhData_1(k) < 0
        PhData_1(k) = 360+PhData_1(k);
    end
end

[Divya]

No errors now, thanks a lot!

Regards,

Divya

[Voss]

You're welcome!