CVXPY
Maximize
  x
Subject To
 12: PnormApprox(x, 2) <= 1.0
Bounds
 x free
End
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AFTER COMPILATION
OBJECTIVE
  Sense            : minimize
VARIABLES
  [continuous] <x_0>: obj=-1, original bounds=[-inf,+inf]
  [continuous] <x_1>: 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]
CONSTRAINTS
  [linear] <c1>: <x_1>[C] <= 1;
  [linear] <c2>: <soc_t_1>[C] -<x_1>[C] == 0;
  [linear] <c3>: <soc_t_2>[C] -<x_0>[C] == 0;
  [nonlinear] <c4>: <soc_t_2>*<soc_t_2>-<soc_t_1>*<soc_t_1> <= 0;
END
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SCIP
OBJECTIVE
  Sense            : maximize
VARIABLES
  [continuous] <x_0>: obj=1, original bounds=[-inf,+inf]
CONSTRAINTS
  [nonlinear] <12>: ((<x_0>*<x_0>))^0.5 <= 1;
END