Mixing
Defining constraints in Jenetics
I have previously worked with the MOEA Framework, which knows the concept of constraints. That is, a solution to a problem might have a good fitness, but is infeasible. For instance, when working with the knapsack problem, a particular combination of items may lead to a high profit, but their weight exceeds the knapsack's capacity. A corresponding fitness function would include lines like:
// Set the fitness (=> profit) of the solution (=> knapsack).
solution.setObjective(0, profit)
// Set the constrain (=> 0.0 if OK, , otherwise the distance to the boundary).
solution.setConstraint(0, (weight <= capacity) ? 0.0 : weight - capacity)
Another example in case of a multi-objective knapsack problem would be the constraint that a knapsack is not allowed to use items which are already used in another knapsack.
Has Jenetics something similar? Or how could I encode constraints as part of the fitness function (or somewhere else)?
java optimization genetic-algorithm
asked Nov 21 '18 at 12:50
beatngu13beatngu13
1,9221932
add a comment |
I have previously worked with the MOEA Framework, which knows the concept of constraints. That is, a solution to a problem might have a good fitness, but is infeasible. For instance, when working with the knapsack problem, a particular combination of items may lead to a high profit, but their weight exceeds the knapsack's capacity. A corresponding fitness function would include lines like:
// Set the fitness (=> profit) of the solution (=> knapsack).
solution.setObjective(0, profit)
// Set the constrain (=> 0.0 if OK, , otherwise the distance to the boundary).
solution.setConstraint(0, (weight <= capacity) ? 0.0 : weight - capacity)
Another example in case of a multi-objective knapsack problem would be the constraint that a knapsack is not allowed to use items which are already used in another knapsack.
Has Jenetics something similar? Or how could I encode constraints as part of the fitness function (or somewhere else)?
java optimization genetic-algorithm
asked Nov 21 '18 at 12:50
beatngu13beatngu13
1,9221932
add a comment |
I have previously worked with the MOEA Framework, which knows the concept of constraints. That is, a solution to a problem might have a good fitness, but is infeasible. For instance, when working with the knapsack problem, a particular combination of items may lead to a high profit, but their weight exceeds the knapsack's capacity. A corresponding fitness function would include lines like:
// Set the fitness (=> profit) of the solution (=> knapsack).
solution.setObjective(0, profit)
// Set the constrain (=> 0.0 if OK, , otherwise the distance to the boundary).
solution.setConstraint(0, (weight <= capacity) ? 0.0 : weight - capacity)
Another example in case of a multi-objective knapsack problem would be the constraint that a knapsack is not allowed to use items which are already used in another knapsack.
Has Jenetics something similar? Or how could I encode constraints as part of the fitness function (or somewhere else)?
java optimization genetic-algorithm
asked Nov 21 '18 at 12:50
beatngu13beatngu13
1,9221932
I have previously worked with the MOEA Framework, which knows the concept of constraints. That is, a solution to a problem might have a good fitness, but is infeasible. For instance, when working with the knapsack problem, a particular combination of items may lead to a high profit, but their weight exceeds the knapsack's capacity. A corresponding fitness function would include lines like:
// Set the fitness (=> profit) of the solution (=> knapsack).
solution.setObjective(0, profit)
// Set the constrain (=> 0.0 if OK, , otherwise the distance to the boundary).
solution.setConstraint(0, (weight <= capacity) ? 0.0 : weight - capacity)
Another example in case of a multi-objective knapsack problem would be the constraint that a knapsack is not allowed to use items which are already used in another knapsack.
Has Jenetics something similar? Or how could I encode constraints as part of the fitness function (or somewhere else)?
java optimization genetic-algorithm
java optimization genetic-algorithm
asked Nov 21 '18 at 12:50
beatngu13beatngu13
1,9221932
asked Nov 21 '18 at 12:50
beatngu13beatngu13
1,9221932
edited Nov 21 '18 at 16:42
beatngu13
asked Nov 21 '18 at 12:50
beatngu13beatngu13
1,9221932
asked Nov 21 '18 at 12:50
beatngu13beatngu13
1,9221932
asked Nov 21 '18 at 12:50
beatngu13beatngu13
1,9221932
1,9221932
add a comment |
add a comment |
1 Answer
1
active
oldest
votes
Jenetics doesn't support constraints directly. You can set a phenotypeValidator in the Engine.Builder. This will reject Phenotypes and recreate invalid individuals. Not exactly a constraint, but a kind of. The second possibility is to return the minimum fitness value for all objectives for such values.
answered Nov 21 '18 at 15:33
Franz WilhelmstötterFranz Wilhelmstötter
44434
add a comment |
Your Answer
StackExchange.ifUsing("editor", function () {
StackExchange.using("externalEditor", function () {
StackExchange.using("snippets", function () {
StackExchange.snippets.init();
});
});
}, "code-snippets");
StackExchange.ready(function() {
var channelOptions = {
tags: "".split(" "),
id: "1"
};
initTagRenderer("".split(" "), "".split(" "), channelOptions);
StackExchange.using("externalEditor", function() {
// Have to fire editor after snippets, if snippets enabled
if (StackExchange.settings.snippets.snippetsEnabled) {
StackExchange.using("snippets", function() {
createEditor();
});
}
else {
createEditor();
}
});
function createEditor() {
StackExchange.prepareEditor({
heartbeatType: 'answer',
autoActivateHeartbeat: false,
convertImagesToLinks: true,
noModals: true,
showLowRepImageUploadWarning: true,
reputationToPostImages: 10,
bindNavPrevention: true,
postfix: "",
imageUploader: {
brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
allowUrls: true
},
onDemand: true,
discardSelector: ".discard-answer"
,immediatelyShowMarkdownHelp:true
});
}
});
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fstackoverflow.com%2fquestions%2f53412433%2fdefining-constraints-in-jenetics%23new-answer', 'question_page');
}
);
Post as a guest
Required, but never shown
1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
Jenetics doesn't support constraints directly. You can set a phenotypeValidator in the Engine.Builder. This will reject Phenotypes and recreate invalid individuals. Not exactly a constraint, but a kind of. The second possibility is to return the minimum fitness value for all objectives for such values.
answered Nov 21 '18 at 15:33
Franz WilhelmstötterFranz Wilhelmstötter
44434
add a comment |
Jenetics doesn't support constraints directly. You can set a phenotypeValidator in the Engine.Builder. This will reject Phenotypes and recreate invalid individuals. Not exactly a constraint, but a kind of. The second possibility is to return the minimum fitness value for all objectives for such values.
answered Nov 21 '18 at 15:33
Franz WilhelmstötterFranz Wilhelmstötter
44434
add a comment |
Jenetics doesn't support constraints directly. You can set a phenotypeValidator in the Engine.Builder. This will reject Phenotypes and recreate invalid individuals. Not exactly a constraint, but a kind of. The second possibility is to return the minimum fitness value for all objectives for such values.
answered Nov 21 '18 at 15:33
Franz WilhelmstötterFranz Wilhelmstötter
44434
Jenetics doesn't support constraints directly. You can set a phenotypeValidator in the Engine.Builder. This will reject Phenotypes and recreate invalid individuals. Not exactly a constraint, but a kind of. The second possibility is to return the minimum fitness value for all objectives for such values.
answered Nov 21 '18 at 15:33
Franz WilhelmstötterFranz Wilhelmstötter
44434
answered Nov 21 '18 at 15:33
Franz WilhelmstötterFranz Wilhelmstötter
44434
answered Nov 21 '18 at 15:33
Franz WilhelmstötterFranz Wilhelmstötter
44434
answered Nov 21 '18 at 15:33
Franz WilhelmstötterFranz Wilhelmstötter
44434
44434
add a comment |
add a comment |
Thanks for contributing an answer to Stack Overflow!
- Please be sure to answer the question. Provide details and share your research!
But avoid …
- Asking for help, clarification, or responding to other answers.
- Making statements based on opinion; back them up with references or personal experience.
To learn more, see our tips on writing great answers.
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fstackoverflow.com%2fquestions%2f53412433%2fdefining-constraints-in-jenetics%23new-answer', 'question_page');
}
);
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
