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Hi All,

Thanks for keep on reading.

I have found what I was looking for on this thread: The "nil" GPType in
GPNodeConstraints<http://listserv.gmu.edu/cgi-bin/wa?A2=ind0804&L=ecj-interest-l&D=0&X=4753654B9C0978582B&P=855>.
I am indeed trying to add the constraints that my model needs and I'm coming
across some troubles.

Let me *contextualize *the problem. I'm generating a tree of *AND *and
*OR *non-terminal
nodes and a *RULE*-function as terminal nodes. I want to add some constrains
so the generated tree follows this two rules:
 *1)* The root of the tree must be an AND function.
 *2)* At least one of the childs of the non-terminal nodes must be or a
terminal-node (RULE) or an AND node.

I'm trying to add the described constrains like this:

First, I define the GPTypes as follows:

gp.type.a.size = 4

gp.type.a.0.name = nil   # This one might not be necessary

gp.type.a.1.name = rule

gp.type.a.2.name = and

gp.type.a.3.name = or

gp.type.s.size = 0


*To fulfill 1)* I added the follow tree constrain:

gp.tc.0.returns = and


*To fulfill 2)* I added the follow node constrains:

gp.nc.size = 10

#--------------------#

gp.nc.7 = ec.gp.GPNodeConstraints

gp.nc.7.name = ncAND

gp.nc.7.returns = and

gp.nc.7.size = 2

gp.nc.7.child.0 = rule

*gp.nc.7.child.1 = or*

#--------------------#

gp.nc.8 = ec.gp.GPNodeConstraints

gp.nc.8.name = ncRULE

gp.nc.8.returns = rule

gp.nc.8.size = 0

#--------------------#

gp.nc.9 = ec.gp.GPNodeConstraints

gp.nc.9.name = ncOR

gp.nc.9.returns = or

gp.nc.9.size = 2

gp.nc.9.child.0 = rule

*gp.nc.9.child.1 = and*



Then I add each constrains to the functions of the function set:

gp.fs.0.func.0 = ec.app.gp.ossimRuleGeneration.func.Or

gp.fs.0.func.0.nc = *ncOR*


> gp.fs.0.func.1 = ec.app.gp.ossimRuleGeneration.func.rule

gp.fs.0.func.1.nc = *ncRULE*


> gp.fs.0.func.2 = ec.app.gp.ossimRuleGeneration.func.And

gp.fs.0.func.2.nc = *ncAND*



*Note *that with this constrains I am being more restrictive that what I
have defined in 2), and actually* it doesn't work *because, as it is
obvious, it never finish due there is always a non-terminal node as child
in gp.nc.8.child.1 and gp.nc.9.child.1. The problem here is that I
need gp.nc.8.child.1
and gp.nc.9.child.1 to be some times *AND *and some others *RULE*, so the GP
program will eventually finish.

And I will like to set gp.nc.8.child.0 and gp.nc.9.child.0 some times to *RULE
*and some others to *AND *to fully satisfy 2)

Is there any way? How can I do such things.

Thanks in advance.



On Tue, Dec 15, 2009 at 10:08 AM, alibaba <[log in to unmask]> wrote:

>
> Hello!
>
> First of all, thanks for reading.
>
> I need to add some Constraints to my GP program so each function that I
> have can only accept a specific subset of children. For this, should specify
> this on the params files or I have to add some checks on the
> checkConstraints method for each GPNode.
>
> Does anybody know an example on the web about this that I can follow?
>
> Thanks in advance.
>
>