define the cell array size for excel data

i have given different inputs to known variables using excel data to solve the equations, but defining the cell array size i am getting the error.

nX = size(X,1 );
Solutions= cell(1, nX);
for S=1:nX
   Xo=(Xs+(R(S)*Xr))/(1+R(S));
   X =((bt*Qo(S)*(1+R(S))*Xo)+(Y*1000*a*V*J*bs))/(bt*((Qo(S)*(1+R(S)))-((V*Y*k*N)/((Kn*1000)+N))+V*kd));
     eqn1=Qo(S)*(1+R(S))*(No(S)-N)-V*((a*J*1000)+((X*k*N)/((Kn*1000)+N)))==0;
      eqn2=(sqrt((Lstar^1.76)+(5.2*(Nstar-Nstar_min)))-(Lstar^0.88))/2.6==jstar^0.88;
      Solutions=vpasolve([eqn1,eqn2],[N,J]);
   temp = struct2cell(Solutions);
   sold= vpa(horzcat(temp{:}));

[KSSV]

Which line throws error and what error? You have to specify.

[sunitha]

The error is unrecognised variable X and it is showing the error in the line nX=size(X,1)

[KSSV]

Error is clear right? You hve to define the variable X. Error says clearly you have not defined X.

[KSSV]

sunitha commented: i have defined the variable X . The error is showing in the while defining the cell array size.Actually i have defined the variable X in the equation

[KSSV]

X should be defined before the line:

nX = size(X,1 );

Answer 1

[Walter Roberson]

nX = length(R);
Solutions = cell(1, nX);
sold = zeros(nX,2);
for S=1:nX
   Xo=(Xs+(R(S)*Xr))/(1+R(S));
   X =((bt*Qo(S)*(1+R(S))*Xo)+(Y*1000*a*V*J*bs))/(bt*((Qo(S)*(1+R(S)))-((V*Y*k*N)/((Kn*1000)+N))+V*kd));
   eqn1=Qo(S)*(1+R(S))*(No(S)-N)-V*((a*J*1000)+((X*k*N)/((Kn*1000)+N)))==0;
   eqn2=(sqrt((Lstar^1.76)+(5.2*(Nstar-Nstar_min)))-(Lstar^0.88))/2.6==jstar^0.88;
   Solutions{S} = vpasolve([eqn1,eqn2],[N,J]);
   temp = struct2cell(Solutions{S});
   sold(S,:) = double(horzcat(temp{:}));
end

[sunitha]

Tw