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XPRBgetctrrng

XPRBgetctrrng


Purpose
Get ranging information for a constraint.
Synopsis
double XPRBgetctrrng(XPRBctr ctr, int rngtype);
Arguments
ctr 
Reference to a previously created constraint.
rngtype 
The type of ranging information sought. This is one of:
XPRB_UPACT 
upper activity (= the level to which the constraint activity may be increased at a cost per unit of increase given by the XPRB_UUP value, ignoring the upper bound on the constraint as specified by its RHS);
XPRB_LOACT 
lower activity (= the level to which the constraint activity may be decreased at a cost per unit of decrease given by the XPRB_UDN value, ignoring the lower bound on the constraint as specified by its RHS);
XPRB_UUP 
upper unit cost;
XPRB_UDN 
lower unit cost.
Return value
Ranging information of the required type.
Example
The following returns the upper activity value of the constraint ctr1.
XPRBprob expl2;
XPRBctr ctr1;
double upact;
expl2 = XPRBnewprob("example2");
ctr1 = XPRBnewctr(expl2, "r1", XPRB_E);
 ...
XPRBlpoptimize(expl2, "");
upact = XPRBgetctrrng(ctr1, XPRB_UPACT);
Further information
This method can only be used after solving an LP problem. Ranging information for MIP problems can be obtained by fixing all discrete variables to their solution values and re-solving the resulting LP problem.
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