Source code for picos.constraints.con_rsoc

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# Copyright (C) 2018-2019 Maximilian Stahlberg
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"""Rotated second order cone constraints."""

from collections import namedtuple

from .. import glyphs
from ..apidoc import api_end, api_start
from ..caching import cached_property
from .constraint import ConicConstraint

_API_START = api_start(globals())
# -------------------------------

[docs]class RSOCConstraint(ConicConstraint): """Rotated second order cone membership constraint."""
[docs] def __init__(self, normedExpression, upperBoundFactor1, upperBoundFactor2=None, customString=None): """Construct a :class:`RSOCConstraint`. :param ~picos.expressions.AffineExpression normedExpression: Expression under the norm. :param ~picos.expressions.AffineExpression upperBoundFactor1: First of the two scalar factors that make the upper bound on the normed expression. :param ~picos.expressions.AffineExpression upperBoundFactor2: Second of the two scalar factors that make the upper bound on the normed expression. :param str customString: Optional string description. """ from ..expressions import AffineExpression if upperBoundFactor2 is None: upperBoundFactor2 = AffineExpression.from_constant(1) assert isinstance(normedExpression, AffineExpression) assert isinstance(upperBoundFactor1, AffineExpression) assert isinstance(upperBoundFactor2, AffineExpression) assert len(upperBoundFactor1) == 1 assert len(upperBoundFactor2) == 1 = normedExpression self.ub1 = upperBoundFactor1 self.ub2 = upperBoundFactor2 super(RSOCConstraint, self).__init__( self._get_type_term(), customString, printSize=True)
def _get_type_term(self): return "RSOC"
[docs] @cached_property def conic_membership_form(self): """Implement for :class:`~.constraint.ConicConstraint`.""" from ..expressions import RotatedSecondOrderCone return (self.ub1 // self.ub2 //, \ RotatedSecondOrderCone(dim=(len( + 2))
Subtype = namedtuple("Subtype", ("argdim",)) def _subtype(self): return self.Subtype(len( @classmethod def _cost(cls, subtype): return subtype.argdim + 2 def _expression_names(self): yield "ne" yield "ub1" yield "ub2" def _str(self): a = glyphs.le(glyphs.squared(glyphs.norm(, glyphs.clever_mul(self.ub1.string, self.ub2.string)) if self.ub1.is1: b =, 0) elif self.ub2.is1: b =, 0) else: b =, self.ub2.string), 0) return glyphs.and_(a, b) def _get_size(self): return (len( + 2, 1) def _get_slack(self): return self.ub1.safe_value * self.ub2.safe_value \ - (abs(**2).safe_value
# -------------------------------------- __all__ = api_end(_API_START, globals())