%matlab script to solve for nodal voltages: inverting op-amp setup
%created by: Circuits class 2018

Ri = 10e3;  
Rf = 50e3;
Vin = 2;

Ao = 100000;
Rin = 1e12;
Ro = 50;



G = [1, 0, 0, 0;...
    0, Ao, 0, 1;...
    1/Ri, -(1/Rf + 1/Ri + 1/Rin), 1/Rf, 0;...
    0, 1/Rf, -(1/Rf + 1/Ro), 1/Ro
     ]
 
 
 I = [Vin; 0; 0; 0 ]
 
 
 %G*V = I form, solve for nodal voltages:
 V = inv(G)*I

%  Note:
 va = V(1) %  = vin
 vb = V(2) % = v-
 vc = V(3)  %=vout
 vd = V(4) % = dependent source output