Does Max Planar 3-SAT admit a PTAS?











up vote
6
down vote

favorite












Suppose we are given a formula $phi$ of 3-SAT, with variables $x_1,dots, x_n$ and clauses $C_1,dots, C_m$. Consider the graph $G_phi$ where there is one node for each clause $C_i$, for each positive literal $x_i$ and for each negative literal $overline{x_i}$. A literal is adjacent to a clause if and only if this clause contains the literal. $phi$ is a planar instance If $G_phi$ is planar.



Max planar 3-SAT is defined as the restriction of Max 3-SAT to planar instances.



This problem is known to be NP-hard. Is this problem also APX-Hard or there exists a known PTAS for this problem ?










share|cite|improve this question







New contributor




Mathieu Mari is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
























    up vote
    6
    down vote

    favorite












    Suppose we are given a formula $phi$ of 3-SAT, with variables $x_1,dots, x_n$ and clauses $C_1,dots, C_m$. Consider the graph $G_phi$ where there is one node for each clause $C_i$, for each positive literal $x_i$ and for each negative literal $overline{x_i}$. A literal is adjacent to a clause if and only if this clause contains the literal. $phi$ is a planar instance If $G_phi$ is planar.



    Max planar 3-SAT is defined as the restriction of Max 3-SAT to planar instances.



    This problem is known to be NP-hard. Is this problem also APX-Hard or there exists a known PTAS for this problem ?










    share|cite|improve this question







    New contributor




    Mathieu Mari is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
    Check out our Code of Conduct.






















      up vote
      6
      down vote

      favorite









      up vote
      6
      down vote

      favorite











      Suppose we are given a formula $phi$ of 3-SAT, with variables $x_1,dots, x_n$ and clauses $C_1,dots, C_m$. Consider the graph $G_phi$ where there is one node for each clause $C_i$, for each positive literal $x_i$ and for each negative literal $overline{x_i}$. A literal is adjacent to a clause if and only if this clause contains the literal. $phi$ is a planar instance If $G_phi$ is planar.



      Max planar 3-SAT is defined as the restriction of Max 3-SAT to planar instances.



      This problem is known to be NP-hard. Is this problem also APX-Hard or there exists a known PTAS for this problem ?










      share|cite|improve this question







      New contributor




      Mathieu Mari is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
      Check out our Code of Conduct.











      Suppose we are given a formula $phi$ of 3-SAT, with variables $x_1,dots, x_n$ and clauses $C_1,dots, C_m$. Consider the graph $G_phi$ where there is one node for each clause $C_i$, for each positive literal $x_i$ and for each negative literal $overline{x_i}$. A literal is adjacent to a clause if and only if this clause contains the literal. $phi$ is a planar instance If $G_phi$ is planar.



      Max planar 3-SAT is defined as the restriction of Max 3-SAT to planar instances.



      This problem is known to be NP-hard. Is this problem also APX-Hard or there exists a known PTAS for this problem ?







      reference-request complexity-classes approximation-algorithms approximation-hardness planar-graphs






      share|cite|improve this question







      New contributor




      Mathieu Mari is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
      Check out our Code of Conduct.











      share|cite|improve this question







      New contributor




      Mathieu Mari is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
      Check out our Code of Conduct.









      share|cite|improve this question




      share|cite|improve this question






      New contributor




      Mathieu Mari is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
      Check out our Code of Conduct.









      asked Nov 20 at 14:12









      Mathieu Mari

      332




      332




      New contributor




      Mathieu Mari is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
      Check out our Code of Conduct.





      New contributor





      Mathieu Mari is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
      Check out our Code of Conduct.






      Mathieu Mari is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
      Check out our Code of Conduct.






















          1 Answer
          1






          active

          oldest

          votes

















          up vote
          9
          down vote



          accepted










          Yes, a PTAS for Max-Planar-3-SAT can be constructed by using Brenda Baker's approach.

          This has been observed, for instance, in Theorem 17 in




          Pierluigi Crescenzi and LucaTrevisan:

          "Max NP-completeness made easy"

          Theoretical Computer Science 28, (1999), Pages 65-79







          share|cite|improve this answer





















            Your Answer





            StackExchange.ifUsing("editor", function () {
            return StackExchange.using("mathjaxEditing", function () {
            StackExchange.MarkdownEditor.creationCallbacks.add(function (editor, postfix) {
            StackExchange.mathjaxEditing.prepareWmdForMathJax(editor, postfix, [["$", "$"], ["\\(","\\)"]]);
            });
            });
            }, "mathjax-editing");

            StackExchange.ready(function() {
            var channelOptions = {
            tags: "".split(" "),
            id: "114"
            };
            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',
            convertImagesToLinks: false,
            noModals: true,
            showLowRepImageUploadWarning: true,
            reputationToPostImages: null,
            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
            },
            noCode: true, onDemand: true,
            discardSelector: ".discard-answer"
            ,immediatelyShowMarkdownHelp:true
            });


            }
            });






            Mathieu Mari is a new contributor. Be nice, and check out our Code of Conduct.










             

            draft saved


            draft discarded


















            StackExchange.ready(
            function () {
            StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fcstheory.stackexchange.com%2fquestions%2f41913%2fdoes-max-planar-3-sat-admit-a-ptas%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








            up vote
            9
            down vote



            accepted










            Yes, a PTAS for Max-Planar-3-SAT can be constructed by using Brenda Baker's approach.

            This has been observed, for instance, in Theorem 17 in




            Pierluigi Crescenzi and LucaTrevisan:

            "Max NP-completeness made easy"

            Theoretical Computer Science 28, (1999), Pages 65-79







            share|cite|improve this answer

























              up vote
              9
              down vote



              accepted










              Yes, a PTAS for Max-Planar-3-SAT can be constructed by using Brenda Baker's approach.

              This has been observed, for instance, in Theorem 17 in




              Pierluigi Crescenzi and LucaTrevisan:

              "Max NP-completeness made easy"

              Theoretical Computer Science 28, (1999), Pages 65-79







              share|cite|improve this answer























                up vote
                9
                down vote



                accepted







                up vote
                9
                down vote



                accepted






                Yes, a PTAS for Max-Planar-3-SAT can be constructed by using Brenda Baker's approach.

                This has been observed, for instance, in Theorem 17 in




                Pierluigi Crescenzi and LucaTrevisan:

                "Max NP-completeness made easy"

                Theoretical Computer Science 28, (1999), Pages 65-79







                share|cite|improve this answer












                Yes, a PTAS for Max-Planar-3-SAT can be constructed by using Brenda Baker's approach.

                This has been observed, for instance, in Theorem 17 in




                Pierluigi Crescenzi and LucaTrevisan:

                "Max NP-completeness made easy"

                Theoretical Computer Science 28, (1999), Pages 65-79








                share|cite|improve this answer












                share|cite|improve this answer



                share|cite|improve this answer










                answered Nov 20 at 15:14









                Gamow

                3,65931230




                3,65931230






















                    Mathieu Mari is a new contributor. Be nice, and check out our Code of Conduct.










                     

                    draft saved


                    draft discarded


















                    Mathieu Mari is a new contributor. Be nice, and check out our Code of Conduct.













                    Mathieu Mari is a new contributor. Be nice, and check out our Code of Conduct.












                    Mathieu Mari is a new contributor. Be nice, and check out our Code of Conduct.















                     


                    draft saved


                    draft discarded














                    StackExchange.ready(
                    function () {
                    StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fcstheory.stackexchange.com%2fquestions%2f41913%2fdoes-max-planar-3-sat-admit-a-ptas%23new-answer', 'question_page');
                    }
                    );

                    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







                    Popular posts from this blog

                    Plaza Victoria

                    Puebla de Zaragoza

                    Musa