function OneNLEexample
clear, clc, format short g, format compact
xguess = 53. ; 
disp('Variable values at the initial estimate');
disp([' Unknown value ' num2str(xguess) '   Function Value ' num2str(NLEfun(xguess))]); 
xsolv=fzero(@NLEfun,xguess); 
disp(' Variable values at the solution');
disp([' Unknown value ' num2str(xsolv) '   Function Value ' num2str(NLEfun(xsolv))]); 
%- - - - - - - - - - - - - - - - - - - - - -
function fT = NLEfun(T); 
P1 = 10 ^ (6.85221 - 1064.63 / (T + 232.0)); 
P2 = 10 ^ (6.87776 - 1171.53 / (T + 224.366)); 
x1 = 0.1; 
x2 = 0.9; 
fT = x1 * P1 + x2 * P2 - 760;