Give "Input data must be a numeric, cell, or logical array" error. How to take data from loop Vpasolve to excel?

How can i take answer of this loop in excel ?

L = Ns*A*k*T 
[num] = xlsread('Isc.xlsx');
F = num
[num] = xlsread('Voc.xlsx');
B = num
VLA = size (F,1);
for i = 1:1:VLA
    for j= 0:9:18
         syms Q
         eq = Q ==  (F(i,1)*(1-(exp(q*(j - B(i,1) + (Q*Rs))/L))));
         sol = vpasolve(eq)
    end
end
xlswrite('C:\Users\S. S.\Desktop\figure', sol)

[Jan]

If you post the complete error message, that readers do not have to guess, in which line the code fails.

By the way, I've formatted the code as code. You can do this by your own in following questions. Thanks.

What is q and Rs?

[Mohammad Sulaiman Stanekzai]

Error using xlswrite (line 166)
Input data must be a numeric, cell, or logical array.
line 166 
theMessage = exceptionHandler(nargout, exception);

q and Rs are (Electron charge and Series Resistance) known.

Thanks by the way.