pwd

ans =

\\nask.man.ac.uk\home$\MATLAB

ls

.                      limited_data_app.fig   
..                     limited_data_app.m     
140311.txt             makemat.m              
20032014.txt           myf.m                  
28-Jan-2015.txt        myfirstmodel.mdl       
PLL                    mymfile.m              
deriv2.m               nag_lsqcurvefit.m      
diary-06-03-2013.txt   nag_lsqcurvefit_aux.m  
diary-13-3-2-2013.txt  opttest.m              
figjunk.fig            ray_tracer_2d.m        
figjunk.m              rubbish.fig            
heat.m                 rubbish.m              
ilaplace.m             siddon.m               
junj.fig               sinc.m                 
junj.m                 startup.m              
junkgraph.fig          test.wav               
junkgraph.m            testwalk.m             
kaczmarz.m             
landweber.m            

edit siddonS
2i

ans =

        0 + 2.0000i

1+3i

ans =

   1.0000 + 3.0000i

1i

ans =

        0 + 1.0000i

img = zeros(16,16);
img(10,5)=1;
imagesc(img)
[A,data]=siddonS(img,20,12);
20*12

ans =

   240

16^2

ans =

   256

[A,data]=siddonS(img,20,15);
imagesc(data)
Ar
{Cannot find an exact (case-sensitive) match for 'Ar'

The closest match is: ar
in C:\Program
Files\MATLAB\R2012a\toolbox\ident\ident\ar.m

} 
Ar = reshape(16,16,20,15);
{Error using <a href="matlab:helpUtils.errorDocCallback('reshape')" style="font-weight:bold">reshape</a>
To RESHAPE the number of elements must not change.
} 
Ar = reshape(A,16,16,20,15);
{Error using <a href="matlab:helpUtils.errorDocCallback('reshape')" style="font-weight:bold">reshape</a>
ND-sparse arrays are not supported.
} 
Ar = reshape(full(A),16,16,20,15);
imagesc(Ar(:,:,8,7))
Ar = reshape(full(A),16,16,15,20);
imagesc(Ar(:,:,8,7))
Ar = reshape(full(A),20,15.16,16);
{Error using <a href="matlab:helpUtils.errorDocCallback('reshape')" style="font-weight:bold">reshape</a>
Size arguments must be real integers.
} 
Ar = reshape(full(A),20,15,16,16);
imagesc(Ar(:,:,4,5))
imagesc(Ar(:,:,4,8))
imagesc(Ar(:,:,1,1))
norm(A * img(:) -date(:))
{Undefined variable date.
} 
norm(A * img(:) -data(:))

ans =

     0

spy
spy(A)
imagesc(A\data(:))
imagesc(reshape(A\data(:),16,16))
imagesc(reshape(A\(data(:)+ 0.01*randn(size(data(:))),16,16))
 imagesc(reshape(A\(data(:)+ 0.01*randn(size(data(:))),16,16))
                                                     |
{Error: Expression or statement is
incorrect--possibly unbalanced (, {, or [.
} 
imagesc(reshape(A\(data(:)+ 0.01*randn(size(data(:))),16,16)))
 imagesc(reshape(A\(data(:)+ 0.01*randn(size(data(:))),16,16)))
                                                     |
{Error: Expression or statement is
incorrect--possibly unbalanced (, {, or [.
} 
imagesc(reshape(A\(data(:)+ 0.01*randn(size(data(:)))),16,16))
d=data(:);
imagesc(reshape(A(1:270,:)\d(1:270))
 imagesc(reshape(A(1:270,:)\d(1:270))
                                    |
{Error: Expression or statement is
incorrect--possibly unbalanced (, {, or [.
} 
imagesc(reshape(A(1:270,:)\d(1:270)))
{Error using <a href="matlab:helpUtils.errorDocCallback('reshape')" style="font-weight:bold">reshape</a>
Not enough input arguments.
} 
imagesc(reshape(A(1:270,:)\d(1:270),16,16))
imagesc(reshape(A(1:200,:)\d(1:200),16,16))
{Warning: Rank deficient, rank = 190, tol =
9.420387e-12.} 
imagesc(reshape(A(1:150,:)\d(1:150),16,16))
{Warning: Rank deficient, rank = 140, tol =
7.582513e-12.} 
imagesc(reshape(A(1:100,:)\d(1:100),16,16))
{Warning: Rank deficient, rank = 92, tol =
5.427373e-12.} 
diary off