Re: [jgap-users] JGAP GP - Variable and Boolean functions

[Klaus M. <jg...@kl...>]

Karthun,
 
GreaterThan returns a boolean exclusively. But you have to specify what the
input type for GreaterThan is (Integer, Double, Boolean, Float,....)
The message you get does not relate to the return type of your whole
program. If you want to avoid it, add the statement
    config.setStrictProgramCreation(false);
(instead of true).

With that I get from your source the solution;
X > 0
 
which is perfect.
 
Best

Klaus
www.klaus-meffert.com <http://www.klaus-meffert.com/> 

 


  _____  

From: Karthun [mailto:vf...@wa...] 
Sent: Tuesday, January 12, 2010 7:28 PM
To: Klaus Meffert
Cc: jga...@li...
Subject: Re: [jgap-users] JGAP GP - Variable and Boolean functions


Hi Klaus, 

Thanks for your answer.

My understanding is that the GreaterThan function must return the same type
than variable vx. I am confused about the semantic of this function
returning an Integer or Double though. I would expect such function
returning a boolean exclusively. This is maybe why I am so confused by GP.

I anyway tried using an Integer as suggested in your reply but I received
the following exception:

Chromosome (depth 0, index 0) requires a function of return type class
java.lang.Integer (sub return type 0) but there is no such node available

This is surprising since the return type of the program should be a Boolean.


Find attached the code I am using for this test case.