How to write geometrical data to a file

Hi, I am in the process of writing a matlab code for creation of a 3D wing. I have been able to write the coordinates onto a file but i dont know how to capture the curves and surfaces onto the file. Currently i have written the coordinates to a .dat file. How do i create the curves by joinging the coordinates and Is there any command to write the leading and trailing edge curves onto the same file???

            for i=1:length(y)
            fprintf(fid,'%f %f %f \n', xle(i), y(i), 0); %points le (0 < y < 22.5)

             end
        for i=1:length(y)
            fprintf(fid,'%f %f %f \n', xte(i), y(i), 0);% points te (0 < y < 22.5)
        end
        fclose(fid);