solving 5 nonlinear equations and getting error
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so i was solving some equations but i keep getting this error
Error using symengine
DOUBLE cannot convert the input expression into a double array.
Error in sym/double (line 613)
Xstr = mupadmex('symobj::double', S.s, 0);
here is the code:
eq1 = (gcr*10^5)/gamma + z(1) - h2...
- (q3^2 - qt^2)/(2*gravity*A^2) - (0.81*f1*(leqtheo1+sum(l(1:5)))*q1^2)/(gravity*(Di*10^-3)^5);
eq2 = qt - (1+sqrt((leqtheo1+sum(l(1:5)))/(leqtheo2+sum(l))))*q3;
eq3 = v3 - q3/A;
eq4 = re3 - (density*v3*Di*10^-3)/viscosity;
eq5 = f3 - 0.316*re3^-0.25;
x3 = solve(eq1,eq2,eq3,eq4,eq5);
Qtheo(3) = double(x3.qt);
Vtheo(3) = double(x3.v3);
Retheo(3) = double(x3.re3);
Ftheo(3) = double(x3.f3);
1 个评论
John D'Errico
2023-5-23
编辑：John D'Errico
2023-5-23
That is not the code, since we cannot execute it. there are many, many undefined variables. How can we know what is in them? And since some of them may contain symbolic expressions themselves, we cannot easily help you.
Make it easy to get help, not difficult. Unless, of course, that is your goal.
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2023-5-23
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