CVXPY
Maximize
  Sum(X * [[2.00 1.00]
 [-2.00 -4.00]], None, False)
Subject To
 14: PnormApprox(X, 2) <= 6.0
Bounds
 X free
End
----------------------------------------
AFTER COMPILATION
OBJECTIVE
  Sense            : minimize
VARIABLES
  [continuous] <x_0>: obj=-2, original bounds=[-inf,+inf]
  [continuous] <x_1>: obj=2, original bounds=[-inf,+inf]
  [continuous] <x_2>: obj=-1, original bounds=[-inf,+inf]
  [continuous] <x_3>: obj=4, original bounds=[-inf,+inf]
  [continuous] <x_4>: obj=0, original bounds=[-inf,+inf]
  [continuous] <soc_t_1>: obj=0, original bounds=[0,+inf]
  [continuous] <soc_t_2>: obj=0, original bounds=[-inf,+inf]
  [continuous] <soc_t_3>: obj=0, original bounds=[-inf,+inf]
  [continuous] <soc_t_4>: obj=0, original bounds=[-inf,+inf]
  [continuous] <soc_t_5>: obj=0, original bounds=[-inf,+inf]
CONSTRAINTS
  [linear] <c1>: <x_4>[C] <= 6;
  [linear] <c2>: <soc_t_1>[C] -<x_4>[C] == 0;
  [linear] <c3>: <soc_t_2>[C] -<x_0>[C] == 0;
  [linear] <c4>: <soc_t_3>[C] -<x_1>[C] == 0;
  [linear] <c5>: <soc_t_4>[C] -<x_2>[C] == 0;
  [linear] <c6>: <soc_t_5>[C] -<x_3>[C] == 0;
  [nonlinear] <c7>: <soc_t_2>*<soc_t_2>+<soc_t_3>*<soc_t_3>+<soc_t_4>*<soc_t_4>+<soc_t_5>*<soc_t_5>-<soc_t_1>*<soc_t_1> <= 0;
END
----------------------------------------
SCIP
OBJECTIVE
  Sense            : maximize
VARIABLES
  [continuous] <X_0_0>: obj=2, original bounds=[-inf,+inf]
  [continuous] <X_0_1>: obj=1, original bounds=[-inf,+inf]
  [continuous] <X_1_0>: obj=-2, original bounds=[-inf,+inf]
  [continuous] <X_1_1>: obj=-4, original bounds=[-inf,+inf]
CONSTRAINTS
  [nonlinear] <14>: ((<X_0_0>*<X_0_0>+<X_0_1>*<X_0_1>+<X_1_0>*<X_1_0>+<X_1_1>*<X_1_1>))^0.5 <= 6;
END