[EvA] (no subject)

[Marcel Kronfeld]

s kumar wrote:
> I am trying to use Eva2 for predicting value for a set of nodes using
> DE. Among the set of nodes some nodes have values and others don’t
> have. I want to predict the value for unknown nodes within the range
> of known values. The known nodes value acts as constraints to the
> system. Apart from that I want certain nodes to have some relation
> with other nodes like less than or equal to etc. The problem is that
> how do I keep the known values of the nodes unmodified and how do I
> set the less than equal to etc constraints. Please guide the same
> using java code.

Hi there,

Im afraid Im not sure what you mean by "nodes". EvA2 uses that notion
within its GP framework, but DE usually works on real valued vectors.
Could you clarify your optimization problem? What does your search space
look like? What does your target function express, what does it look like?

In general, I would not try to code fixed values within the solution
vector - a fixed value would just be a constant within the problem
class, not part of the search space sample.
Relation constraints can be added with the GenericConstraint class. To
express a "less than" relation between two parameters x[i], x[j], you
may add a constraint represented by the string "-(xi,xj)" setting its
type to "lessEqualZero".

Best regards,
  Marcel Kronfeld

-- 
 Dipl.-Inform. Marcel Kronfeld
 Wilhelm-Schickard-Institute for Computer Science
 University of Tuebingen
 Sand 1 - A305, 72076 Tuebingen, Germany

 Phone: (+49/0)-7071-29-78987, Fax: (+49/0)-7071-29-5091
 EMail: marcel.kronfeld at uni-tuebingen.de