[Scip] Strange behavior

[Aurélien Questel]

Hi everyone,
I'm currently working on a B&Price algorithm, using a second scip instance to solve my pricing problem.

I have a strange behavior on some instances.
Here is the output at the end of my pricer solving : 

SCIP Status        : problem is solved [optimal solution found]
Solving Time (sec) : 0.03
Solving Nodes      : 6
Primal Bound       : -1.69360996591490e+10 (2 solutions)
Dual Bound         : -1.69360996591490e+10
Gap                : 0.00 %
[linear] <consCapa>: 0 <= +5<y_11->11>[B] +5<y_11->8>[B] +5<y_11->9>[B] +5<y_12->12>[B] +5<y_12->4>[B] +5<y_12->7>[B] +5<y_12->8>[B] +5<y_12->11>[B] +5<y_11->12>[B] +5<y_13->13>[B] +5<y_13->9>[B] +5<y_13->10>[B] +5<y_14->14>[B] +5<y_14->5>[B] +5<y_14->8>[B] +5<y_14->11>[B] +5<y_11->14>[B] +5<y_15->15>[B] +5<y_15->5>[B] +5<y_15->7>[B] +5<y_15->8>[B] +5<y_15->12>[B] +5<y_12->15>[B] +5<y_16->16>[B] +5<y_16->1>[B] +5<y_16->3>[B] +5<y_16->4>[B] +5<y_16->7>[B] +5<y_16->12>[B] +5<y_12->16>[B] +5<y_17->17>[B] +5<y_17->2>[B] +5<y_17->6>[B] +5<y_17->10>[B] +5<y_17->13>[B] +5<y_13->17>[B] +5<y_18->18>[B] +5<y_18->2>[B] +5<y_18->9>[B] +5<y_18->10>[B] +5<y_18->11>[B] +5<y_11->18>[B] +5<y_18->12>[B] +5<y_12->18>[B] +5<y_19->19>[B] +5<y_19->1>[B] +5<y_19->3>[B] +5<y_19->6>[B] +5<y_19->7>[B] +5<y_19->16>[B] +5<y_16->19>[B] +5<y_20->20>[B] +5<y_20->5>[B] +5<y_20->9>[B] +5<y_20->11>[B] +5<y_11->20>[B] +5<y_20->13>[B] +5<y_13->20>[B] +5<y_20->14>[B] +5<y_14->20>[B] <= 20;
violation: right hand side is violated by 280


I just can't figure how scip can state he found a "best solution" while a constraint of the original problem is violated ?
(on this solution all my 'y' variables are set to 1, and other original constraints are violated too)
Do you have any clue where my mistake can be ?

It happens when I use all the plugins : 
   SCIP_CALL( SCIPincludeDefaultPlugins(_scipPricer) );
   /* include 2 connexity constraint handlers */
	SCIP_CALL( SCIPincludeObjConshdlr(_scipPricer, new QRing2ConCliHdlr(_scipPricer, _Pd), FALSE) );

Or only these ones : 

 SCIP_CALL( SCIPincludeConshdlrLinear(_scipPricer) ); 
 SCIP_CALL( SCIPincludeConshdlrIntegral(_scipPricer) );
 SCIP_CALL( SCIPincludeNodeselBfs(_scipPricer) );
 SCIP_CALL( SCIPincludeReaderCip(_scipPricer) );

 /* DISPLAY *
 SCIP_CALL( SCIPincludeDispDefault(scip) );
 SCIP_CALL( SCIPincludeDialogDefault(scip) );
 /* include 2 connexity constraint handlers */
 SCIP_CALL( SCIPincludeObjConshdlr(_scipPricer, new QRing2ConCliHdlr(_scipPricer, _Pd), FALSE) );



Thanks for all

Best, 

Aurélien Questel


PS : the statistics are joint to this mail 


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