stlwrite error using reshape

Hey im having issue with my code, getting the error:

Error using reshape Product of known dimensions, 9, not divisible into total number of elements, 28362.

Error in stlwrite (line 81) facets = reshape(facets(:,faces'), 3, 3, []);

I tried to change it from 3,3 so it whould work but it mess everything even more...

Here is my code:

    clf
  file = 'pattern3';
  switch file
      case 'pattern2'
      P = imread('Pattern2.png');
      P = repmat(P,3);
      case 'pattern3'
      P = imread('Pattern3.png');
      P = P(400:3400, 400:3400);
      P = 255 - P*6;
      case 'pattern4'
      P = imread('Pattern4.jpg');
      case 'banksy'
      P = imread('Banksy.png');
      P = padarray(P, [500 500], 255);
  end

P = 1-im2bw(P);
Nmin = min(size(P));
P = P(1:Nmin, 1:Nmin);
[xg, yg] = meshgrid(1:Nmin, 1:Nmin);
P((xg - Nmin/2).^2 + (yg - Nmin/2).^2 > 0.99*0.25*Nmin^2) = 0;
P = padarray(P, [1 1], 0);

CC = bwconncomp(P);

dtheta    = pi/24;
theta     = (-pi:dtheta:(pi-dtheta))';
nodeouter = [1.1*cos(theta) 1.1*sin(theta)];
Nnodes    = length(nodeouter);
nodelist  = (1:Nnodes)';
allnodes  = nodeouter;
alledges  = [nodelist , mod(nodelist, Nnodes)+1];

for n = 1:CC.NumObjects
%for n = 2:2
    newP = zeros(size(P));
    newP(CC.PixelIdxList{1,n}(:)) = 1;
    newP = filter2(fspecial('average',5),newP);
    C = contourc(newP,[0.2 0.2]);
    C = C(:,2:end)';
    C2 = dpsimplify(C,1);
    m = 1;

      while m <= length(C2(:,1))
         if(C2(m,1) == 1 || C2(m,2) == 1)
             C2(m,:) = [];
         else
             m = m + 1;
         end
      end

      C2 = (C2 - Nmin/2)/(Nmin/2);
      C = (C - Nmin/2)/(Nmin/2);
      figure(1)
      hold all
      plot(C2(:,1), C2(:,2))
      axis image xy
      drawnow

      nodeinner  = C2;
      Nnodeshole = length(nodeinner);
      nodelist   = (1:Nnodeshole)';
      edgelist   = [nodelist , mod(nodelist, Nnodeshole)+1];
      edgelist   = edgelist + Nnodes; 

      allnodes   = [allnodes; nodeinner];
      alledges   = [alledges; edgelist];
      Nnodes     = Nnodes + Nnodeshole;
      n
  end
hdata.fun = @(x,y) 0.05*(1 + ((x.^2 + y.^2)/a^2)).^2;
[p,t] = refine2(allnodes, alledges);
as = 0.5;

for n = 1:length(as)
a = as(n);
h = 0;

x = p(:,1);
y = p(:,2);
z = zeros(size(x));
r = sqrt(x.^2 + y.^2);
phi = atan2(y,x);
theta = atan(r/(a+h));
alpha = 2*theta;

xnew = a*sin(alpha).*cos(phi);
ynew = a*sin(alpha).*sin(phi);
znew = -a*cos(alpha);

p2 = [xnew, ynew, znew];
stlwrite('Test.stl', t, p2)

fv.faces = t;
fv.vertices = p2;
clf
figure(3)
patch(fv, 'FaceColor', [1 1 1], 'EdgeColor', 'black', 'LineWidth', 0.1)
axis equal
axis off
xlim([-a a])
ylim([-a a])
zlim([-a a])
camlight head
view(58,28)
zoom(1.5)
drawnow
%print(gcf, [num2str(n) '.png'], '-dpng', '-r250')
end

[KSSV]

Try to take number elements which are exactly divisible by 9.

Answer 1

[DGM]

This problem happens because you're trying to write an STL file consisting of line segments, not triangles. Early versions of FEX #20922 (and others) will fail with a reshaping error if the mesh is not triangular.

The second output of refine2() is not a list of triangular faces; it's a 2-column edge list. You probably need the third argument instead.

[p,~,t] = refine2(allnodes, alledges);

That said, there are no comments and no input data, so I don't know whether that solves all the problems. Without knowing what it's supposed to do, I can't know if it's doing it correctly.