Scippy

SCIP

Solving Constraint Integer Programs

SCIP_Ratio Struct Reference

Detailed Description

branching encoding of a variable's ratio A variable's ratio is defined based upon its left and right LP gains, as the unique root > 1 of the polynomial x^r - x^(r-l) -1, where l and r are the left and right LP gains. We store the root as upratio^(invleft), with invleft = 1/l. The value upratio is thus the ratio of the variable (1, r/l). An extra boolean stores whether the encoded ratio is valid, i.e. there were no numerical problems when computing it

Definition at line 126 of file treemodel.c.

Data Fields

SCIP_Real upratio
 
SCIP_Real invleft
 
SCIP_Bool valid
 

Field Documentation

◆ upratio

SCIP_Real SCIP_Ratio::upratio

"UnPowered" ratio, i.e. the ratio of the characteristic polynomial with gains (1, rightgain/leftgain)

Definition at line 128 of file treemodel.c.

Referenced by computeSampleTreesize(), computeSVTS(), computeVarRatio(), and hasBetterRatio().

◆ invleft

SCIP_Real SCIP_Ratio::invleft

"INVerse left gain, i.e. 1/leftgain

Definition at line 130 of file treemodel.c.

Referenced by computeSampleTreesize(), computeSVTS(), computeVarRatio(), and hasBetterRatio().

◆ valid

SCIP_Bool SCIP_Ratio::valid

True iff the ratio computed is valid

Definition at line 131 of file treemodel.c.

Referenced by computeSampleTreesize(), computeSVTS(), computeVarRatio(), hasBetterRatio(), and selectCandidateUsingRatio().