% this is example 1.9.4 page 121:  solving problems in chem
% they are wrong

disp('column 1 is methane')
disp('column 2 is ammonia')
disp('column 3 is water')
disp('column 4 is glycine')
disp('column 5 is diatomic hydrogen')
disp(' ')

disp('here are the number of atoms in each molecule')
disp('row 1 is hydrogen')
% 4*a + 3*b + 2*c = 5*d + 2*e
disp('row 2 is carbon')
% a=2*d;
disp('row 3 is oxygen')
% c=2*d;
disp('row 4 is nitrogen')
% b=d;

disp('note - the negative values indicate transposition from right side')


mm=  [ 4     3     2    -5    -2
       1     0     0    -2     0
       0     0     1    -2     0
       0     1     0    -1     0 ]

mm2=rref(mm)

[n,d]=rat(mm2(:,5))

disp('2 parts methane + 1 part ammonia + 2 parts water')
disp('gives 1 part glycine and 5 parts molecular hydrogen')