Error in muPAD command

please help me about this error :

??? Error using ==> mupadmex

Error in MuPAD command: DOUBLE cannot convert the input expression into a double array.

If the input expression contains a symbolic variable, use the VPA function instead.

This error appears for this code calculating Y1.

for beta = 1:2

syms zbar

zbarc = double(int((((70e9-427e9)*(zbar/0.1*(2e-9))^beta+427e9)/(1-((0.3-0.17)*(zbar/0.1*(2e-9))^beta+0.17)^2))*zbar, 0, 0.1*(2e-9))/(int((((70e9-427e9)*(zbar/0.1*(2e-9))^beta+427e9)/(1-((0.3-0.17)*(zbar/0.1*(2e-9))^beta+0.17)^2)), 0, 0.1*(2e-9))));

Y1 = double(int ((((70e9-427e9)*(zbar/0.1*(2e-9))^beta+427e9)/(1-((0.3-0.17)*(zbar/0.1*(2e-9))^beta+0.17)^2)).*(zbar-zbarc),0,0.1*(2e-9)));

end

Thank you.

Answer 1

[Walter Roberson]

You could get that error if int() is not able to find a closed form solution for the integral, and numeric integration also finds itself not able to come up with a solution (e.g., if it diverges). In that combination of circumstances, conversion to floating point form would fail.