MATLAB: I’m having trouble loading a cell array within the for loop

cell arraysplotting

I'm trying to load a cell array with one column of arrays and one column of single strings and whose entries are defined at each n value of a for loop. I defined the dimensions of the cell array then tried to assign the inputs of the nth iteration to the nth row and appropriate column. I cant imagine why when I run the code my cell array comes out with empty inputs!! Additionally when I try to plot the cell array(2nd loop) I get the error message "Index exceeds matrix dimensions." and I don't understand why this is happening.
for n = (1:length(tnew));
    R = [cos(statesnew(n,4))     sin(statesnew(n,4));
         -sin(statesnew(n,4))    cos(statesnew(n,4))]; 
    phi = (0:pi/40:2*pi)';
    Geometry = r*[cos(phi) sin(phi);
                  NaN NaN;
                  -1/1.75 + 1/25*cos(phi), 1/1.75 + 1/25*sin(phi)
                  NaN NaN;
                  (-1/2 + 1/8) + 1/25*cos(phi), 1/2 + 1/25*sin(phi);
                  NaN NaN;
                 -1/2 + 1/25*cos(phi), (1/2 - 1/8) + 1/25*sin(phi);]; 
             %Creates a circle with three smaller circles placed in an 
             %equilateral tringle that will all rotate and translate when 
             %the other arrays/matrices manipulate it. 
    Rotation = Geometry*R'; %applying the rotation matrix to the geometry
    Translation = ones(length(Geometry),1)*statesnew(n,2)*[1 0]; 
    %Creates an array of same length as the geometry
    %array that places the x value of the current timestep in the first row
    %so that is can be added to the x coordinate of every point of the
    %geometry
    NetMotion = Translation + Rotation; %rotating and translating the ball         
    if abs(statesnew(n,1) + (statesnew(n,3)*(-r))) < 0.0044;
         Color = 'R';
    else 
        Color = 'B';
    end    %If point of contact is about zero then the red bowling ball 
    %change its color to blue
    NetMotionArray = cell(n,2);
    NetMotionArray{n,1} = NetMotion;
    NetMotionArray{n,2} = Color;
    %Setting up a cell array so that the 4 referenced dimensions can be 
    %hidden in a two dimensional array
end
 for n = [1:length(tnew)]
    figure(4)
    plot((NetMotionArray{n,1}(:,1)), (NetMotionArray{n,1}(:,2)), NetMotionaArray{n,2} ); 
    axis ([-1 10 -10 10]);
    pause(.035);
 end

Best Answer

Hi Dominic, I think you overwrite your cell array NetMotionArray with every iteration loop with line:
NetMotionArray = cell(n,2);
What this line means is that for every iteration loop you initialize new NetMotionArray and replace the old one.This line should be moved from inside a for loop to top of your code and should be changed to:
NetMotionArray = cell(length(tnew),2);
Let me know if that solved your problems.
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