%
% CONDVP  Inf-condition of Vandermonde
%   matrix V(x) of order n with nonnegative
%   nodes
%
%      x(1)>x(2)> ... >x(n)>=0
%
function c=condVp(n,x)
u=zeros(n,1);
for i=1:n
  u(i)=i;
end
for i=1:n
  s(i)=sum(x.^(i-1));
  x0=x(find(u-u(i)));
  p(i)=prod((1+x0)./abs(x(i)-x0));
end
c=max(s)*max(p);
