[Scip] branching on constraints

[Alessia Violin]

Hello,

solving my problem with branch&price I would like to change the 
branching. Now I am branching on binary variables x_a^k = sum_j l_a^j * 
x_a^k,j <= 1, simply defining them as binary in the variable definition 
as they do not occur in the pricing. The variables for the pricing are 
l_a^j, and x_a^k,j are parameters that I calculate during the pricing.

As those x_a^k variables are added only for the branching, I would like 
to eliminate them and branch directly on constraints sum_a l_a^j * 
x_a^k,j <=1 (they can be 0 or 1).

Does it exist already in SCIP a branching rule on constraints? If not, 
shall I do it defining a new branching rule or is there an easier way to 
do it?

Thank you in advance for any help and suggestion,

Alessia

-- 
Alessia Violin
Service Graphes et Optimisation Mathématique (G.O.M.)
Université Libre de Bruxelles
C.P. 210/01
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Tel: 02 650 58 80 - Fax: 02 650 59 70
Email: aviolin at ulb.ac.be
Webpage: http://homepages.ulb.ac.be/~aviolin/