From: Gordon on
I Think thereĀ“s mitake in line 2

>1 v = a.*x.^2 + b.*y.^2 + c.*z.^2 + ...
>2 d.*x.*y + e.*x.*z + f.*x.*y.*z + ...
> 3 g.*x + h.*y + i.*z + j;

Correct is this code:
1 v = a.*x.^2 + b.*y.^2 + c.*z.^2 + ...
2 d.*x.*y + e.*x.*z + f.*y.*z + ...
3 g.*x + h.*y + i.*z + j;

Greetings from A-Town

Gordon