Regarding the Fit_Ellipse Program

Greetings all!
The last time I posted here I got awesome help and I have what I
believe is a smaller problem this time.
I am trying to use the fit_ellipse program (http://www.dfanning.com/
ip_tips/fit_ellipse.html) and having some difficulty in that my ROI is
a contour defined by a 2-D array and not a 1-D array of pixels.
My 2-D array contains the x and y positions of all the points along
that contour (or ROI) so I am trying to translate this fit_ellipse
program to something I can use.

Would really appreciate the help!
Bruno