 | 1 | initial version |
Hello,
I use sage 7.1 on a debian computer. I am trying to use the sdp solver, but:
p = SemidefiniteProgram()
omega = p.new_variable()
p.set_objective(omega[0])
p.add_constraint(matrix(1,[1]) * omega[0] <= matrix(1,[1]))
p.add_constraint(matrix(1,[1]) * omega[1] <= matrix(1,[1]))
p.show()
returns an error:
ValueError: need more than 1 value to unpack
What does it mean?
Antoine
| | 2 | No.2 Revision |
Hello,
I use sage 7.1 on a debian computer. I am trying to use the sdp solver, but:
p = SemidefiniteProgram()
omega = p.new_variable()
p.set_objective(omega[0])
p.add_constraint(matrix(1,[1]) * omega[0] <= matrix(1,[1]))
p.add_constraint(matrix(1,[1]) * omega[1] <= matrix(1,[1]))
p.show()
returns an error:
ValueError: need more than 1 value to unpack
What does it mean?
Antoine
After some tests...
I don't understand what happens but here are some tests I have done:
The sdp solver works when I put all the variables in the objective. So it works with:
p = SemidefiniteProgram()
omega = p.new_variable()
p.set_objective(omega[0] + 0*omega[1])
p.add_constraint(matrix(1,[1]) * omega[0] <= matrix(1,[1]))
p.add_constraint(matrix(1,[1]) * omega[1] <= matrix(1,[1]))
p.show()
If I put the objective after the constraints I get the error again. For example with
p = SemidefiniteProgram()
omega = p.new_variable()
p.add_constraint(matrix(1,[1]) * omega[0] <= matrix(1,[1]))
p.add_constraint(matrix(1,[1]) * omega[1] <= matrix(1,[1]))
p.set_objective(omega[0] + 0*omega[1])
p.show()
I get the error
ValueError: need more than 1 value to unpack
To conclude it means that I need to know all the variables x I will use in my sdp and add 0*x to the objective. It works like that but if someone can explain me the error I would be happy !
Antoine
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