You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: Sanket_CT_Project.m
    path of file: ./repos/CT-Image-Reconstruction/src
    
    the code of the file until where you have to start completion: %	Biomedical Imaging: CT project
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%   CREATE DISK PHANTOM AND SINOGRAM
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%   Parameters for the disk phantom a
    
function to realise it as an array and not a vector
   plot(projection);
   axis([0,na,0,2*projection_max]);
   title('0th moment')
   xlabel('X Position')
   ylabel('Attenuation')
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%   IMPLEMENT SIMPLE BACKPROJECTION, i.e. 
%                PRODUCE LAMINOGRAMS
%
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%
 disp('Simple backprojection')
if 1~=exist('lamin')
 
  lamin = zeros(nx,ny);  
  for ia = 1:na
    disp(sprintf('angle %g of %g', ia, na));   
    projection_ia=sinogram(:,ia);   %each angle projection
    projection_smear=repmat (projection_ia,1,128);  %smear current angle in 128*128
   rot= imrotate(projection_smear', ia*180/256, 'bicubic','crop');  %256 projections correspond to 180 deg. Hence ia*180/256 for current projection angle
    lamin=lamin+rot;     %lamin needs to be 128*128 = so 1st arg in imrotate should be same dimension
  end