# Problem with solve function

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Maruthi prasanna C on 16 Mar 2020
Answered: Stephan on 16 Mar 2020
syms s vs v1 v2 vo s R1 R2 R3 Rc1 Rc2 gm1 gm2 gm3 gmc1 gmc2 C1 C2 Cc1 Cc2 k1 k2;
% Nodal Analysis Equations
eq1 = '-gm1*vs + v1/R1 + v1*s*C1 - v2/(1/(s*Cc1)+Rc1)+ vo/(1/(s*Cc2)+Rc2)=0'
eq2 = 'gm2*v1 + v2/R2 + v2/(1/(s*Cc1)+Rc1) + v2*s*C2=0'
eq3 = 'gm3*v2 + vo/R3 + vo/(1/(s*Cc2)+Rc2) + vo*s*C3=0'
[v1,v2,vo]=solve(eq1,eq2,eq3,v1,v2,vo);
eq1 =
'-gm1*vs + v1/R1 + v1*s*C1 - v2/(1/(s*Cc1)+Rc1)+ vo/(1/(s*Cc2)+Rc2)=0'
eq2 =
'gm2*v1 + v2/R2 + v2/(1/(s*Cc1)+Rc1) + v2*s*C2=0'
eq3 =
'gm3*v2 + vo/R3 + vo/(1/(s*Cc2)+Rc2) + vo*s*C3=0'
Error using solve>getEqns (line 418)
List of equations must not be empty.
Error in solve (line 226)
[eqns,vars,options] = getEqns(varargin{:});
Error in ThreeStageIndirectCompensation_Class_A (line 17)
[v1,v2,vo]=solve(eq1,eq2,eq3,v1,v2,vo);
>>
Maruthi prasanna C on 16 Mar 2020
Need to know what doesn error "List of equations must not be empty." mean & fix for it

Stephan on 16 Mar 2020
syms s vs v1 v2 vo s R1 R2 R3 Rc1 Rc2 gm1 gm2 gm3 gmc1 gmc2 C1 C2 C3 Cc1 Cc2 k1 k2;
% Nodal Analysis Equations
eq1 = -gm1*vs + v1/R1 + v1*s*C1 - v2/(1/(s*Cc1)+Rc1)+ vo/(1/(s*Cc2)+Rc2)==0
eq2 = gm2*v1 + v2/R2 + v2/(1/(s*Cc1)+Rc1) + v2*s*C2==0
eq3 = gm3*v2 + vo/R3 + vo/(1/(s*Cc2)+Rc2) + vo*s*C3==0
[v1,v2,vo]=solve(eq1,eq2,eq3,v1,v2,vo)

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