Scippy

SCIP

Solving Constraint Integer Programs

Detailed Description

power and signed power expression handlers

Author
Benjamin Mueller

Definition in file expr_pow.h.

#include "scip/scip.h"
#include "scip/type_expr.h"

Go to the source code of this file.

Functions

SCIP_RETCODE SCIPincludeExprhdlrPow (SCIP *scip)
 
SCIP_RETCODE SCIPincludeExprhdlrSignpower (SCIP *scip)
 
void SCIPaddSquareLinearization (SCIP *scip, SCIP_Real sqrcoef, SCIP_Real refpoint, SCIP_Bool isint, SCIP_Real *lincoef, SCIP_Real *linconstant, SCIP_Bool *success)
 
void SCIPaddSquareSecant (SCIP *scip, SCIP_Real sqrcoef, SCIP_Real lb, SCIP_Real ub, SCIP_Real *lincoef, SCIP_Real *linconstant, SCIP_Bool *success)
 
Power and signed power expression

These expression handler provide the power function, that is,

\[ x \mapsto \begin{cases} x^e & \textrm{if}\; x \geq 0\; \textrm{or}\; e\in\mathbb{Z}, \\ \textrm{undefined}, & \textrm{otherwise}. \end{cases} \]

and the signed power function, that is,

\[ x \mapsto \textrm{sign}(e) |x|^e \]

for some exponent \(e\).

SCIP_RETCODE SCIPcreateExprPow (SCIP *scip, SCIP_EXPR **expr, SCIP_EXPR *child, SCIP_Real exponent, SCIP_DECL_EXPR_OWNERCREATE((*ownercreate)), void *ownercreatedata)
 
SCIP_RETCODE SCIPcreateExprSignpower (SCIP *scip, SCIP_EXPR **expr, SCIP_EXPR *child, SCIP_Real exponent, SCIP_DECL_EXPR_OWNERCREATE((*ownercreate)), void *ownercreatedata)
 
SCIP_Bool SCIPisExprSignpower (SCIP *scip, SCIP_EXPR *expr)
 

Function Documentation

◆ SCIPaddSquareLinearization()

void SCIPaddSquareLinearization ( SCIP scip,
SCIP_Real  sqrcoef,
SCIP_Real  refpoint,
SCIP_Bool  isint,
SCIP_Real lincoef,
SCIP_Real linconstant,
SCIP_Bool success 
)

computes coefficients of linearization of a square term in a reference point

Parameters
scipSCIP data structure
sqrcoefcoefficient of square term
refpointpoint where to linearize
isintwhether corresponding variable is a discrete variable, and thus linearization could be moved
lincoefbuffer to add coefficient of linearization
linconstantbuffer to add constant of linearization
successbuffer to set to FALSE if linearization has failed due to large numbers

Definition at line 3226 of file expr_pow.c.

References FALSE, NULL, REALABS, SCIP_Real, SCIPaddSquareSecant(), SCIPfloor(), SCIPisInfinity(), and SCIPisIntegral().

Referenced by addBilinearTermToCut(), addRltTerm(), buildPowEstimator(), and SCIPisExprSignpower().

◆ SCIPaddSquareSecant()

void SCIPaddSquareSecant ( SCIP scip,
SCIP_Real  sqrcoef,
SCIP_Real  lb,
SCIP_Real  ub,
SCIP_Real lincoef,
SCIP_Real linconstant,
SCIP_Bool success 
)

computes coefficients of secant of a square term

Parameters
scipSCIP data structure
sqrcoefcoefficient of square term
lblower bound on variable
ubupper bound on variable
lincoefbuffer to add coefficient of secant
linconstantbuffer to add constant of secant
successbuffer to set to FALSE if secant has failed due to large numbers or unboundedness

Definition at line 3294 of file expr_pow.c.

References FALSE, NULL, REALABS, SCIP_Real, SCIPgetExponentExprPow(), SCIPisInfinity(), and SCIPisLE().

Referenced by addBilinearTermToCut(), addRltTerm(), buildPowEstimator(), and SCIPaddSquareLinearization().