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Is symbolic variable limited under 5?

When I setup a Vector with 4 symbolic variables, it is ok. But an error happens for 5 variable, the detail is posted at below. Is the symbolic variable limited below 5?

My code for 5 variables: 

const Variable x0{"x0"};
const Variable x1{"x1"};
const Variable x2{"x2"};
const Variable x3{"x3"};
const Variable x4{"x4"};
  
Eigen::Matrix<Variable, 5, 1> x(x0,x1,x2,x3,x4);

Results: 
error: no matching constructor for initialization of 'Eigen::Matrix<Variable, 5, 1>'
Eigen::Matrix<Variable, 5, 1> x(x0,x1,x2,x3,x4);
Solution

  • This has nothing to do with symbolic variable, the problem is that Eigen doesn't provide a constructor for a vector with 5 entries. You cannot do Eigen::Matrix<double, 5, 1> x(1, 2, 3, 4, 5) either

    You could do

    Eigen::Matrix<symbolic::Variable, 5, 1> x;
x << x0, x1, x2, x3, x4;