Hi again,

first of all, thanks for the quick response! The CVS version works
great -- I should have checked it first... Sorry for that.

I have one more question: is there any way for me to define
probabilities without making any destinction between terminal and
non-terminal nodes and constraints?

For example (and considering the parametrization below), i'd like
GPNodeConstraint nc1 (terminal) to be selected with a probability of
10%, nc2 (terminal) with a probability of 20%, and nc3 (non-terminal)
with a probability of 70%.

----- EXAMPLE PARAMETERIZATION -----
gp.type.a.size = 2
gp.type.a.0.name = A
gp.type.a.1.name = B

gp.nc.size = 4
# NT B
gp.nc.0 = ec.gp.GPNodeConstraints
gp.nc.0.name = nc0
gp.nc.0.returns = B
gp.nc.0.size = 1
gp.nc.0.child.0 = A
# T A
gp.nc.1 = ec.gp.GPNodeConstraints
gp.nc.1.name = nc1
gp.nc.1.returns = A
gp.nc.1.size = 0
gp.nc.1.prob = 0.1
# T A
gp.nc.2 = ec.gp.GPNodeConstraints
gp.nc.2.name = nc2
gp.nc.2.returns = A
gp.nc.2.size = 0
gp.nc.2.prob = 0.2
# NT A
gp.nc.3 = ec.gp.GPNodeConstraints
gp.nc.3.name = nc3
gp.nc.3.returns = A
gp.nc.3.size = 1
gp.nc.3.child.0 = A
gp.nc.3.prob = 0.7

gp.fs.0.size = 4
gp.fs.0.func.0 = functionFiles.FFB1
gp.fs.0.func.0.nc = nc0
gp.fs.0.func.1 = functionFiles.FFA1
gp.fs.0.func.1.nc = nc1
gp.fs.0.func.2 = functionFiles.FFA2
gp.fs.0.func.2.nc = nc2
gp.fs.0.func.3 = functionFiles.FFA3
gp.fs.0.func.3.nc = nc3
-----

Thanks again for the help,

José


On Tue, Oct 14, 2008 at 17:57, Sean Luke <[log in to unmask]> wrote:
> A few months back I made modifications to PTC1 and PTC2 to make them more
> robust for exactly your purposes.  I don't know if those versions are on the
> current ECJ snapshot yet -- they're definitely on CVS. Before we go further
> here, let's make sure that you've got the most recent versions and things
> are still having problems.
>
> Sean
>
> José Carlos B. Ribeiro wrote:
>>
>> Hi,
>>
>> I've been using ECJ for performing some experiments with
>> Strongly-Typed GP (namely, for evolving unit-test cases for Java
>> programs).
>>
>> I wanted to perform some experiments that require setting different
>> probabilities of selecting constraints, and I found out that the PTC1
>> and PTC2 algorithms allow me to do this. However, I've been having
>> some problems.
>>
>> Please consider the parametrization below. Basically, I want
>> GPNodeConstraint nc1 to be chosen with a probability of 30% and nc2 to
>> be selected with a probability of 70%.
>>
>> ----- EXAMPLE PARAMETERIZATION -----
>> gp.type.a.size = 2
>> gp.type.a.0.name = A
>> gp.type.a.1.name = B
>>
>> gp.nc.size = 3
>> gp.nc.0 = ec.gp.GPNodeConstraints
>> gp.nc.0.name = nc0
>> gp.nc.0.returns = B
>> gp.nc.0.size = 1
>> gp.nc.0.child.0 = A
>>
>> gp.nc.1 = ec.gp.GPNodeConstraints
>> gp.nc.1.name = nc1
>> gp.nc.1.returns = A
>> gp.nc.1.size = 0
>> gp.nc.1.prob = 0.3
>>
>> gp.nc.2 = ec.gp.GPNodeConstraints
>> gp.nc.2.name = nc2
>> gp.nc.2.returns = A
>> gp.nc.2.size = 0
>> gp.nc.2.prob = 0.7
>>
>> gp.fs.0.size = 3
>> gp.fs.0.func.0 = functionFiles.FFB1
>> gp.fs.0.func.0.nc = nc0
>> gp.fs.0.func.1 = functionFiles.FFA1
>> gp.fs.0.func.1.nc = nc1
>> gp.fs.0.func.2 = functionFiles.FFA2
>> gp.fs.0.func.2.nc = nc2
>> -----
>>
>> When I tried this out I got the following error message:
>> "java.lang.ArithmeticException: Distribution has no elements". I guess
>> that the problem here is that I didn't define any non-terminals for
>> the atomic type A, and no terminals for B. Everything works fine if
>> both A and B have terminals and non-terminals.
>>
>> The problem is that my problem requires me to define some types that
>> only have terminal nodes (like A). Is there any way for me to get
>> around this? Or am I missing something?
>>
>> Thanks, in advance, for your help,
>>
>> José
>