Power cone

In linear algebra, a power cone is a kind of a convex cone that is particularly important in modeling convex optimization problems. It is a generalization of the quadratic cone: the quadratic cone is defined using a quadratic equation (with the power 2), whereas a power cone can be defined using any power, not necessarily 2.

Definition

The n-dimensional power cone is parameterized by a real number 0<r<1. It is defined as:

Pn,r,1−r:={𝐱∈ℝn:  x1≥0,  x2≥0,  x1r⋅x21−r≥x32+⋯+xn2}

An alternative definition is

Pr,1−r:={𝐱𝟏,𝐱𝟐,𝐱𝟑:  x1≥0,  x2≥0,  x1r⋅x21−r≥|x3|}

Applications

The main application of the power cone is in constraints of convex optimization programs. There are many problems that can be described as minimizing a convex function over a power cone.

References

  1. 1 2 3 "MOSEK Modeling Cookbook - the Power Cones".
  2. ↑ Nesterov, Yurii (2006). Towards nonsymmetric conic optimization.