How do you convert Matlab data into a DXF hole pattern?

I am currently working on a project that I will need to have professionally water-jetted. Because of the large number of holes required, I cannot generate a DXF file using a standard CAD program on my computer. I was able to generate the pattern I want easily enough, but can't seem to get the DXF conversion portion correct. I have used related posts on this subject but am at a loss as to where I went wrong. Thanks in advance for any help.

%Fibonacci hole pattern calculator
n=1:13000; %quantity larger than total amount of holes 
dmin=.18; %min spacing between holes
D=18; %Max diamter
off=.3; %edge offset
rmax=(D/2)-off;%outer radius of pattern
rmin=.75; %min inner radius
Phi=137.50776*pi/180;
rh=.0625; %radius of hole
% constant to mulitply r by.^-1
c=dmin/sqrt((sqrt(n(3))*cos(Phi*3)-sqrt(n(1))*cos(Phi))+(sqrt(n(3))*sin(Phi*3)-sqrt(n(1))*sin(Phi)))*(.17/.207);                                                      
rtemp=c.*sqrt(n);
[j i]=find(rtemp>rmax);%find r to satisfy rmax. j=junk
[j k]=find(rtemp<rmin);%r to satisfy rmin biggest k =start of pattern
r=rtemp(length(k):i-1);
j=length(k):(i-1);
phi=137.50776*pi/180*j;% irrational golden ratio angle approx. 
x=r.*cos(phi); % main equation
y=r.*sin(phi);
a=(2*pi/length(j)).*j; %alpha for circle
x2=(D/2).*sin(a);% x and y for circle
y2=(D/2).*cos(a);

%Start DXF portion
fullname=sprintf('pat.dxf');
fid=fopen(fullname,'w');
fprintf(fid,'0\n SECTION\n 2\n ENTITIES\n');
for a=1:length(x)-1
    fprintf(fid,'0\n CIRCLE\n 8\n 0\n');
    fprintf(fid, '10\n %f\n 20\n %f\n 30\n 0.0\n 40\n .0625\n ', x(a),y(a));
end
fprintf(fid,'endsec\n 0\nEOF\n');
fclose(fid);