using JuMP,Gurobi
n=4
PL=[0.3;0.55;0;0]
model=Model(Gurobi.Optimizer)
G=[1.04209 -0.588235 -0.0 -0.453858;-0.588235 1.069 0 -0.480769;-0 0 0 0;-0.453858 -0.480769 0 0.934627]
Q=[-8.24288 2.35294 3.66667 1.89107; 2.35294 -4.72738 0.0 2.40385;3.66667 0.0 -3.33333 0.0; 1.89107 2.40385 0.0 -4.26159]
@variable(model, U[1:n])
@variable(model, P[1:n])
@variable(model, Ang[1:n])
@variable(model, Angle[1:n,1:n])
@constraint(model, con5[i = 1:n, j = 1:n], Angle[i,j]==Ang[i] .-Ang[j])
@expression(model, my_expr, P-PL)
@NLconstraint(model,co1,my_expr==U.*((G.*cos.(Angle)+Q.*sin.(Angle))*U))
error:
Is P-PL wrong? How could I solve it?